bluuebunny/crossref_metadata_2025 huggingface dataset:
Multicomponent Kinetic Analysis of Trace Metal Binding Sites on Iron Hydrous Oxide Colloids
Authors: Gutzman Donald W. , Langford Cooper H.
Published: March 2019

The adsorption of copper(II) on a hydrous oxide colloid of iron formed by base hydrolysis in the presence of the adsorbate metal has been studied in two ways. Filtration-AAS of equilibrated solutions yielded data which fit well to a single variant adsorption isotherm even at high adsorbate metal concentration thus precluding the need for multivariant fitting. These same colloidal species were kinetically analyzed by reaction of copper with the chromophore reagent EHTTT (a = 13700 Mࢤ1 cmࢤ1 at 434 nm) which revealed the presence of three components, other than the very labile “free” species. Kinetic differentiation of thermodynamically similar sites may result from diffusion control of metal ion release.
Effects of Algae on the Aquatic Persistence of Fenitrothion
Authors: Caunter Terrence , Weinberger Pearl
Published: March 2019

The persistence of the photolytically degradable pesticide fenitrothion (O,O-dimethyl-O-(3-methyl-4-nitrophenyl) phosphorothioate) in aquatic systems was examined to determine whether its t½ could be modulated by the algae Chlamydomonas segnis (Ettl). Sorption of 14C ring labelled fenitrothion into live and freeze-killed algae was monitored under lighted and darkened conditions.

In living algae held under natural sunlight (800 wmࢤ2), an optimal uptake of 9.4 ug 14C ring label mgࢤ1 algae was obtained following 3.75 hours compared to 0.7 µg 14C ring label mgࢤ1 uptake by algae maintained in the dark. Live algae maintained under Vita Lite high intensity fluorescent lamps (Dura Test, 40 wmࢤ2, 290-700 nm) sorbed fenitrothion more slowly. Optimal uptake of 16.6 µg 14C ring label mgࢤ1 algae was obtained after 24 hours compared to 0.8 µg 14C ring label mgࢤ1 algae in sets in the dark. The same phenomenon was observed with freeze-killed cells, where uptake in natural sunlight and Vita Lite® lamps was significantly enhanced (15.7 and 28.8 μg 14C ring label mgࢤ1 algae, respectively) compared to cells maintained in the dark (1.6 and 2.3 µg 14C ring label mgࢤ1 algae, respectively).

The t½ of fenitrothion in the aquatic media without algae was 30.7 hours whereas with live algae in the media the t½ decreased to 15.8 hours.

Photolytic degradation and sorption of fenitrothion were both augmented in the light exposed sets containing algae, thus significantly affecting the t½ of the fenitrothion in the water compartment.
National Water Quality Index Network Options to Consider
Authors: Kwiatkowski Roy E.
Published: March 2019

Canada’s federal water quality program is aimed at providing information for the management of Canada’s water resources to maximize social and economic benefits of these resources for Canadians while ensuring an adequate level of water quality. Adequate being defined as non-impairment of the most sensitive use. The extent of pollution from anthropogenically developed chemicals has become readily apparent over the last decade. As a result in recent years public anxiety about the environment particularly about water quality has increased dramatically. Water pollution issues are no longer solely restricted to the local or regional level. Issues are now discussed at the national, international and global level. As a result, the Water Quality Branch (WQB), Inland Waters Directorate, Department of the Environment, is establishing a National Water Quality Index Network, to provide scientific information and advice to water managers on water quality issues on a national scale. This paper outlines WQB’s present activities and the process used to develop the WQB’s National Water Quality Index Network.
Temporal Variability of Phosphorus Levels in the Flathead River at the International Border
Authors: MacDonald D.D. , Valiela D. , Brown S.J.
Published: March 2019

A three year study of water quality in the boundary reach of the Flathead River was undertaken to determine the temporal variability of total phosphorus (TP) and total dissolved phosphorus (TDP) levels. This investigation, designed to provide information for the development of a compliance monitoring program. Involved intensive sampling of TP and TDP over the spring freshet period and intermittently over the low flow period. In addition, three 24 hour studies were undertaken to assess short-term variability. TP and TDP concentrations ranged from <0.002 to 0.48 mg/l and from <0.002 to 0.035 mg/l, respectively, with the highest levels recorded at the peak of freshet. Over the low flow period the concentrations of both variables were consistently near the detection limit (0.002 mg/1). Fluctuations in the levels of both TP and TDP were positively correlated with changes in streamflow, and reflect increases in suspended sediment concentrations. These results indicate that monitoring programs designed to assess compliance with water quality objectives must take into account the natural variability of phosphorus levels.
Distribution of Organic Contaminants in Water and Suspended Solids of the Rainy River
Authors: Merriman John C.
Published: March 2019

Water and suspended solid samples were collected in 1986 at three stations on the Rainy River and from the final effluents of two bleached kraft pulp and paper mills discharging into the river. A wide range of organic contaminants were analysed, including organochlorine pesticides (OCs), total PCBs, chlorobenzenes (CBs), polycyclic aromatic hydrocarbons (PAHs) and chlorophenols (CPs). Suspended solids were also analysed for dioxins and furans. Analysis of the data indicated that for the most part, compounds were below the detection limit at the upstream end of the river. High levels of PCBs, dioxins, furans, CPs and PAHs were found in mill effluents, which resulted in some elevated concentrations in the Rainy River downstream of the mills. At the downstream end of the river, there was no impact evident for the compounds analysed.
Accumulation of Trace Metals in Three Species of Fish from Lakes in New Brunswick and Nova Scotia (Canada): Influence of pH and Other Chemical Parameters
Authors: Peterson R. H. , Sreedharan A. , Ray S.
Published: March 2019

Brook trout (Salvelinus fontinalis), white sucker (Catostomus commersonii) and yellow perch (Perca flavescens) from headwater lakes in New Brunswick and Nova Scotia (Canada) were analyzed for whole body concentrations of Pb, Cd, Hg, Cu and Zn. Fish from western New Brunswick generally had lowest concentrations of metals. Mercury concentrations were highest in fish from lakes close to urban centers on the leeward side. Only trout were collected from lakes in Cape Breton Island, and these were characterized by high Cd and Zn concentrations. The only consistently strong correlation between metal concentration and any lake chemistry parameter was a negative correlation between Pb concentration and lake pH. Copper and Zn were consistently positively correlated for all three species, perhaps due to their common existence in mineral deposits.
Mixing Characteristics of the Niagara River Plume in Lake Ontario
Authors: Murthy C. R. , Miners K. C.
Published: March 2019

Data collected between 1982 and 1985 from Lagrangian drifter experiments in which about ten drifters were tracked for ten to twelve hours from their release across the Niagara River mouth, and from concurrently taken ship-based temperature soundings at fixed grid stations off the river mouth, are used to develop a conceptual model of the mixing characteristics of the Niagara River in Lake Ontario. The data obtained suggest a three-stage mixing process. In the initial stage, the river inflow momentum dominates and the plume is well mixed vertically. In the intermediate stage, the interaction of the well mixed, buoyant river plume with colder water from deeper depths of the lake generates a sharp thermal front. In the final stage, the river plume responds to the prevailing winds and the general circulation of the lake. The correlation between these observed plume characteristics and the distribution of toxic contaminants such as mercury and mirex in Lake Ontario sediments attributed to Niagara River outflow is illustrated.
The Application of Chemically Modified Fused Silica Fibers in the Extraction of Organics from Water Matrix Samples and their Rapid Transfer to Capillary Columns
Authors: Belardi Robert P. , Pawliszyn Janusz B.
Published: March 2019

A technique for water sample analysis is presented which uses chemically modified fused silica optical fibers as micro solid phase extractors. The small size of the fibers (100 µm o. d. ) allows for direct introduction into the on column injector port of a high resolution gas chromatograph (GC), where the analytes are thermally desorbed. This eliminates the need for solvents and syringes which are used in liquid-liquid or solid phase extraction techniques. Thus, this method lowers cost and analysis time per sample, as well as eliminates possible sources of error. Results show that the efficiency and selectivity of this technique are dependent upon the thickness and polarity of the stationary phase. Initial results indicate that the limit of detection for 2-naphthol and FID detection is approximately 5 ng/g with a linear response range of 5 orders of magnitude.
Treatment of a Petrochemical Wastewater in an Anaerobic Packed Bed Reactor
Authors: Parker W. , Farquhar G. J.
Published: March 2019

Wastewater from a used oil rerefinery was tested in laboratory scale anaerobic packed bed reactors for TOC removal, gas production and control of volatile organic emissions. The raw wastewater had a TOC ranging from 3,250 to 5,800 mg/L of which 40 to 45% consisted of total phenolics, acetone, methanol, ethanol and volatile fatty acids. The remaining TOC was not analyzed but was expected to contain potentially harmful constituents. Treatment of the undiluted wastewater achieved acidogenisis but methane production appeared to have been inhibited. A 1:2 dilution of the wastewater produced reasonably good treatment with 52 to 67% TOC reduction, over 75% removal of acetone and total phenolics and vigorous methane production. Operational parameters were characterized by an organic loading of 1.4 kg COD/m3.d and HRT of 3.0 days. Implications for full-scale operation and airborne contaminant control are discussed
An Economic Analysis of Conservation Tillage as a Sediment Control Strategy on Southwestern Ontario Cropland
Authors: Fox Glenn , Dickson Ed
Published: March 2019

This study compares the costs and benefits of conservation tillage as a means of reducing sediment loading in the Thames River watershed. Conservation tillage systems were found to reduce the wealth of farmers in that the present value of net returns to land under conservation tillage were always found to be less than the present value of net returns using conventional tillage systems based on fall moldboard ploughing. Costs to farmers were more than offset, however, by the reduction of off-farm damages from sediment.
Costs and Consequences of Uncontrolled Toxic Waste Sites Along The Niagara River
Authors: Sudar Anne , Muir Tom
Published: March 2019

Three basic options are considered for dealing with the four largest toxic waste sites along the Niagara River, Hyde Park, Love Canal, 102nd Street, and S-Area. The options are: 1) status quo; 2) containment; and 3) removal and destruction. The costs and consequences of each option are discussed, and looked at from the viewpoint of long and short time horizons as well as the viewpoint of who pays and who benefits.
The Application of Ecological Modelling to Toxic Contaminants and Ecosystem Stress
Authors: Halfon Efraim
Published: March 2019

This review analyzes the application of ecological modelling to problems concerning toxic contaminants and ecosystem stress and explains the purpose and methods of the systems ecology approach, which could be useful to individuals involved in data gathering activities. The review provides operational definitions of ecosystem stress, gives a description of methods of the systems approach and analyzes several topics of interest such as the application of expert system methods in the environmental field and methods of ranking. Recommendations are given to managers in charge of monitoring activities can benefit by interacting with systems ecologists. Four topics are analyzed in detail:

1) Ecosystem stress. To assess the impact that toxic contaminants have on ecosystems we must give an operational definition of ecosystem stress and how to observe it.

2) The purpose and methods of the systems ecology approach.

3) The application of artificial intelligent methods in the environmental field.

4) Methods of ranking.
Developments in Legislation Related to Treatment of Petroleum Refinery Effluents: A U.S. Overview
Authors: Laffly Genevieve
Published: March 2019

Regulatory requirements in the United States controlling wastewater pollutants and toxicity resulting from point sources, such as refineries, emanated from passage of the Federal Water Pollution Control Act in 1972 and its subsequent amendments, collectively referred to as the Clean Water Act. The Clean Water Act empowers in the federal U.S. Environmental Protection Agency and states to issue effluents limitation guidelines and water quality standards to point sources that discharge pollutants directly to surface waters. These guidelines and standards are contained in permits issued under the National Pollutant Discharge Elimination System. The current regulatory emphasis on toxics probably will lead to more stringent pretreatment standards and reduced refinery wastewater flow.
Optimization and Control Petroleum Refinery Wastewater Treatment Systems — Status, Trends and Needs
Authors: Nutt Stephen G.
Published: March 2019

Based on discussions in workshop sessions, several recurring themes became evident with respect to the optimization and control of petroleum refinery wastewater treatment systems to achieve effective removal of toxic contaminants. It was apparent that statistical process control (SPC) techniques are finding more widespread use and have been found to be effective. However, the implementation of real-time process control strategies in petroleum refinery wastewater treatment systems is in its infancy. Considerable effort will need to be expended to demonstrate the practicality of on-line sensors, and the utility of automated process control in petroleum refinery wastewater treatment systems. This paper provides a summary of the discussions held at the workshop.
An Integrated Dynamic Model and Control System for Activated Sludge Wastewater Treatment Plants Part II — Control Systems
Authors: Vitasovic Zdenko , Andrews John F.
Published: March 2019

Part I of this paper has presented an integrated dynamic model for the activated sludge process consisting of a mixture of standard engineering equations and theoretical mechanistic models. In this, Part II of the paper, the integrated model is used in computer simulations to explore process dynamics and integrated control strategies. The interactions of six individual controllers: DO, MCRT, the STOUR profile, settler flow, the compressor, and a pump station have been studied as well as interactions between plant components and design and operation. Among these interactions are those between fluctuations in the influent flow rate and the solids-liquid separator and STOUR in each portion of the biological reactor. The use of a variable volume biological reactor is proposed to damp the effects of flow rate fluctuations on the separator and thus improve effluent quality. Estimation of the STOUR profile and its use in process control is proposed for producing a sludge with more consistent settling characteristics. It is proposed that the use of separator flow control, air flow rate distribution, and step feed capabilities for process control be further explored by field studies for possible incorporation in new plant designs.
The Adaptation of Anaerobic Granulated Bed to Changes in Loading Rate and Liquid Upflow Velocity in UASB Reactors
Authors: Kosaric N. , Blaszczyk R. , Orphan L.
Published: March 2019

Four 20L UASB reactors, R1, R2, R3 and R4 were operated at different upflow velocities of 0.25, 1.0, 1.5, and 0.5 m/h, respectively. Changes in loading rate were achieved by removing part of granules from the bed at a constant volumetric feed rate of 6.2 g COD/(L day).

It was found that the granulated bed may adapt to the increased organic loading rate up to about 1.6 kg COD/(kg VSS day) and achieve a 100% conversion of the COD present (composed of volatile fatty acids). Increasing the loading rate over the above value can bring about a decreased COD conversion. At the organic loading rate of 1.6 kg COD/(kg VSS day), the accumulation of granules in reactors R1 and R4 was observed. At the same loading rate, no accumulation of granules was observed in reactor R2 (within 40 days) and in reactor R3 (within 55 days).

It was also found that a great number of large granules were washed out from reactors R1 and R4 when the loading rate of about 0.7 kg COD/(kg VSS day) was maintained for about 70 days.
A Comparison of the Aquatic Toxicity of Fenitrothion Flowable and Fenitrothion Liquid Technical Formulations
Authors: Ernst W.R. , Doe K.G.
Published: March 2019

Fenitrothion, a popular spruce budworm (Choristoneura fumiferarna) insecticide, has recently been produced as a “flowable” formulation which consists of finely milled particles of the active ingredient in suspension. In order to determine if such a formulation change could alter the chemical’s toxicity and bioconcentration potential to non-target aquatic fauna, a series of bioassays was undertaken. In acute (48- and 96-h LC50s) tests using rainbow trout (Oncorhynchus mykiss), threespine stickleback (Gasterosteus aculeatus), freshwater clams (Anodonta spp.), blue mussels (Mytilus edulis) and the water flea (Daphnia magna), the toxicity of conventional fenitrothion (liquid technical) formulations was not substantially different from that of the “flowable” (particulate) formulation. The exception was that the flowable formulation was less toxic than the liquid technical formulation to the freshwater clam by a factor of 1/3 to 1/5.

Bioconcentration factors to blue mussels for the flowable formulation (15 to 36) were approximately 1/8 to 1/2 the blue mussel bioconcentration factors previously reported for the liquid technical formulations. The results indicate that the flowable formulation does not represent an increased hazard to the aquatic organisms tested, compared with the conventional liquid technical formulations.
Impact of an Acid Spill on the Resident Fauna of the York River and its Recovery
Authors: Prairie R. , Schiefer K. , Moulins L.J. , Chapados V.
Published: March 2019

As a result of a sulphuric acid spill in June 1982 at the Mines Gaspé operation in Murdochville, Québec, water quality of effluents being discharged into the headwaters of the York River was temporarily impaired. It rapidly became apparent that the aquatic fauna of this important Atlantic salmon river had been affected in some areas. This paper provides an overview of the results obtained in biological studies (Atlantic salmon population and benthic communities) carried out by Beak Consultants Ltd. and Noranda Technology Centre, annually, from 1982 to 1985. The biological and water chemistry surveys carried out during this four-year period indicated a short duration event of high dissolved metal levels, primarily copper, shortly after the spill, followed by a rapid improvement in water quality. Both the aquatic macroinvertebrate benthos and fish life in the river were negatively impacted. The nature and degree of this impact as well as the subsequent recolonization of aquatic habitats by both groups were observed and documented.

The most affected aquatic groups in 1982 were the youngest salmon age classes (0+ and 1+) along with the intermediate and sensitive benthic communities. This impact was mainly observed in the upper and middle river section. Maintenance of suitable water quality during the following years has permitted excellent survival rates for juvenile salmon and recolonization of benthic habitats by sensitive species. This has contributed to the gradual re-establishment of a natural aquatic fauna in the York River.

More recent surveys carried out since 1985 confirm that the quality of the York River ecosystem has been maintained and suggest that the survival rates observed for juvenile salmon are higher than the theoretical values usually used in salmon production models.
Coliphage Presence in Various Types of Potable Water in Thailand
Authors: Sivaborvorn Komol , Dutka B.J.
Published: March 2019

Three types of drinking water used in Thailand, tap water, rain water and deep well water (200 m) were tested for bacteriological and coliphage content. 13.5% of the samples contained only coliphage and 13% contained both coliphage and total coliforms. The incidence of coliphage in these potable water supplies reflect the probability of human pathogenic virus also surviving in these waters. The H2S paper-strip test was found to be an equally sensitive indicator of coliform presence compared to MF and MPN total coliform procedures.
The Saguenay Fjord: A Third Factor in the Toxic Chemical Contamination of the St. Lawrence River Estuary
Authors: Allan R.J.
Published: March 2019

The Saguenay Fjord enters the north shore of the St. Lawrence River estuary. The St. Lawrence River is one source of a variety of toxic metals and organic chemicals to its estuary. Some of these chemicals are transported by the river from its source in Lake Ontario and others are added along its course. However, the second major source of water inflow to the St. Lawrence Estuary is the Saguenay Fjord, which is by no means free of contamination. This paper overviews the types of toxic metals and organic chemical contamination and sources in the fjord proper and upstream in its drainage basin. The principal contaminants recorded in bottom sediments are polyaromatic hydrocarbons and mercury. An extensive forest products industry may also be a source of toxic chlorinated organic chemicals. The combined (peak) inputs of these chemicals to the Saguenay Fjord system was in the past and may have continued for many years, even decades. The relationship between the type of contaminants introduced in the past to the St. Lawrence estuary by the St. Lawrence River and the Saguenay Fjord may have implications concerning contamination of the beluga whale population which is located most frequently in the estuary near the fjord inflow.
Trends in Nutrients, Major Ions and Physical Water Quality Parameters in the Niagara River During the 1977–87 Period
Authors: Kuntz K.W. , Tsanis I.K.
Published: March 2019

This paper presents the seasonal and annual variations of the physical parameters, nutrients and major ions in the Niagara River for a period of eleven years, 1977–87. The discharge during this period was found to be steadily increasing and as a consequence the specific conductance was decreasing due to the higher dilution effect, as well as the lower concentrations of chloride and sodium. High concentrations of total phosphorus during the winter months corresponded with high turbidity. In addition, a steady decrease in total phosphorus concentrations was observed until 1984, while during the rest of the period concentrations were increasing. Nitrate nitrogen concentrations were found to be steadily increasing during the entire period except for 1987. Seasonal cycles of specific conductance, calcium, alkalinity, magnesium, and sulphate all showed decreases in April, May and June, during the high discharge period. Both chloride and sodium concentrations have decreased substantially during the 1977–85 period, the result of upstream industrial input decreases, but concentrations since then have levelled out.
Treatment of Oily Waters Using Peat
Authors: Viraraghavan T. , Mathavan G.N.
Published: March 2019

Peat offers itself as an effective medium in the treatment of oily waters, due to its known capacity to remove oil and its abundant availability in Canada. Horticultural peat produced by the Saskatchewan Minerals was used in this study to assess its potential for the removal of oil from various oil-in-water emulsions. The representative oil-in-water emulsions included the following: (1) Medium viscous (130 cP) standard mineral oil (SMO), (2) low viscous (50 cP) Midale crude oil (MCO), cutting oil (CO) and (4) refinery effluent (RE).

Batch kinetic studies were conducted to identify equilibrium time and isotherm patterns. The adsorption of oil by peat was well represented by the BET isotherm compared to the Langmuir and the Freundlich equations. Column studies were conducted using a 100 mm diameter, 600 mm long acrylic pipe with 300 mm depth peat bed. Initially eight-hour tests were run for three different flow rates of 12, 48 and 300 mL/min (2.13, 8.52 and 53.28 m/d). These column studies showed that removal of oil varied between 34 and 99 percent depending upon the influent oil concentration, the type of emulsion, and the flow rate.

Breakthrough studies were undertaken for an optimum flow rate of 50 mL/min (8.88 m/d) for SMO and MCO and 25 mL/min (4.44 m/d) for CO and RE to assess the ultimate capacity of peat under dynamic conditions. The data obtained from breakthrough studies were applied to scale-up and kinetic models to estimate the amount of peat required to remove oil from a flow rate of 150 m3/d of oily waters.
A Phytotoxicity Biosensor using Photosynthetic Membranes
Authors: Purcell Marc , Carpentier Robert
Published: March 2019

The potential of a photoelectrochemical cell employing photo-synthetic membranes in an application as a phytotoxicity biosensor is demonstrated. In this cell, a small volume (80 μl) of isolated thylakoid membranes is used to produce a photocurrent. The reduced species produced during photosynthetic electron transport are oxidized by soluble electroactive mediators which are reoxidized by a platinum working electrode. The photocurrent generated was inhibited by relatively low concentrations of herbicides, nitrite, sulfite and several heavy metals due to their inhibitory effect on photosynthetic electron transport. The cell sensitivity was enhanced when chlorophyll concentration was reduced and artificial electron acceptor concentration was increased.
Simple Models of the Circulation, Dissolved Metals, Suspended Solids and Nutrients in Halifax Harbour
Authors: Petrie Brian , Yeats Philip
Published: March 2019

Salinity data collected in monthly surveys over a two year period are used to model the horizontal circulation and vertical exchange in Halifax Harbour. The circulation is characterised by near-surface outflow and subsurface inflow at rates of order 1 cm s−1; vertical velocities are found to be up to 2 m d−1. Boundary conditions for 5 metals, suspended solids and nutrients are used with the circulation model to derive the distributions of these variables in the Harbour. The modelled distributions of Cu, suspended solids, nitrate and phosphate agree well with the observations. The derived distribution of Mn, Zn, Pb and Hg are less satisfactory, the differences arising because of the chemical dynamics of the former and the uncertainty of the boundary conditions for the latter three. Nitrogen, mostly in the form of ammonia, from sewage can account for a significant portion of the primary productivity in the Harbour; however, the model overestimates the observed winter concentrations of ammonia by a factor of 3.
Fate of Trifluralin in Anaerobic Sediment from an Alberta Farm Dugout
Authors: Fox M.E. , Tol C. Van , Prepas E.E. , Nagy E. , Murphy T.P.
Published: March 2019

Anaerobic surficial sediment from a farm dugout in central Alberta was treated with sufficient Treflan™6 herbicide added to yield 5 µg/g dry weight trifluralin (TRF) and maintained in the laboratory under anaerobic conditions. Samples collected at intervals over 32 days were analysed for trifluralin and related compounds. More than 95% of the trifluralin disappeared within two days but levels then stabilized and even increased slightly, suggesting regeneration from an initially unextractable form. A product of reductive transformation, α, α, α-trifluoro-5-nitro-N4, N4-dipropyltoluene-3,4-diamine (R1TRF), was identified. R1TRF was found from day 0, reached a maximum of 0.3 µg/g, then slowly declined over the duration of the study. A second reductive transformation product, α, α, α-trifluoro-N4, N4-dipropyltoluene-3,4,5-triamine (R2TRF), was also identified. This compound appeared transiently in low concentrations between day 2 and day 16 of the study. The findings of this study were used to explain the bioaccumulation of TRF and related compounds in leeches from a Treflan treated dugout.
Survival of Selected Aquatic Insects Exposed to Methoxychlor Treatment of the Saskatchewan River System
Authors: Dosdall Lloyd M.
Published: March 2019

Survival of aquatic insects was compared before and after exposure to methoxychlor treatment (0.3 mg·L−1 for 15 min) of the Saskatchewan River system at three sites downstream from injection (21, 38, and 107 km). Species studied were Isoperla bilineata (Say), Isoperla longiseta Banks (Plecoptera: Perlodidae), Hydropsyche alternans (Walker), Hydropsyche occidentalis Banks (Trichoptera: Hydropsychidae), Stenonema termination (Walsh), and Stenacron interpunctatum (Say) (Ephemeroptera: Heptageniidae). Survival of individuals exposed to treatment was species-dependent and related to distance from the methoxychlor injection point. At the km 21 site, survival of four of the six species studied declined significantly (P < 0.05) over 15 days, relative to controls. At the km 38 and 107 sites, survival was not affected significantly (P > 0.05) for any species studied.
Mercury and Organochlorinated Hydrocarbons in Surficial Sediments of the St. Francis
Authors: Sloterdijk Harm H.
Published: March 2019

In order to evaluate the role of Lake St. Francis as a depositional zone for toxic substances coming from Lake Ontario and the international section of the St. Lawrence River, a sediment survey was carried out in the early eighties. Samples from 98 stations were analyzed for particle size, organic carbon, mercury (Hg), polychlorinated biphenyls (PCB’s), and organo-chlorinated pesticides, and those from 10 stations for chlorobenzenes, pentachlorophenol, and polybrominated biphenyls. Only PCB’s and Hg were found at high concentrations, up to 1900 and 1500 ng·g−1, respectively. Although Lake Ontario remains a general source of contaminants (especially PCB’s and mirex) for the Quebec stretch of the St. Lawrence River, its contribution to Lake St. Francis is of less importance than that of local sources along the Canada/USA international section of the rivers, such as Cornwall (Hg) and the Massena area (PCB’s).
Evaluation of a Small-Scale Biofilm Process for Wastewater Treatment
Authors: Banerji Shankha K. , Cho Kye-Min
Published: March 2019

An innovative aerated biofilm process (ABP) was evaluated under laboratory conditions to treat synthetic wastewater. The particular system performed well (>90% BOD removal) at fairly high BOD loading conditions (16.7 g BOD m−2d−1). The process did not require a separate secondary settling chamber to produce an effluent low in suspended solids (<10 mgL−1). The amount of sludge produced was lower than other comparable systems — 0.3g total solids were produced per g of BOD removed at an organic removal rate of 8 g BOD m−2d−1. This process could be adopted for treating wastewater in small systems.
Sorption and Desorption of Cu(II) by Ganoderma Lucidum
Authors: Matheickal Jose T. , Iyengar Leela , Venkobachar C.
Published: March 2019

Experimental results on the uptake of Cu(II) by Ganoderma lucidum (M) and its alkali treated residue (Mc) indicated that the metal binding is a fast reaction. The pH of the sorption media affect the metal binding capacity. The equilibrium data for both M and Mc appear to fit well, the Langmuir isotherm. A simple mathematical model is developed based on adsorption equilibria and mass balance to predict the concentration of metal that can be desorbed. Disagreement between the model predicted and experimental desorption equilibria indicated that biosorption of Cu(II) by M and Mc is irreversible. EDTA and HCl are efficient eluants capable of recovering almost all the bound metal.
Aquatic Environmental Aspects of Non-Pesticidal Organotin Compounds
Authors: Maguire R. James
Published: March 2019

Non-pesticidal organotin compounds in Canadian commerce are those of monomethyltin, dimethyltin, monobutyltin, dibutyltin, monooctyltin and dioctyltin. A review is presented of the uses, methods of analysis, environmental occurrence and aquatic toxicity of these compounds, which are scheduled for assessment under the Canadian Environmental Protection Act. It is likely that the most important non-pesticidal route of entry of these compounds to the environment will be through leaching of organotin-stabilized poly(vinyl chloride) by water. Monomethyltin and dimethyltin are widespread in the global environment. Monobutyltin and dibutyltin have been found frequently in harbours, marinas and shipping channels in Canada and elsewhere, arising largely as degradation products from the use of the antifouling agent tributyltin which is now regulated in Canada. There are few reports in the literature on the occurrence of butyltin species as a result of non-pesticidal uses or uses of tributyltin other than as an antifouling agent. Monooctyltin and dioctyltin have not been found to date in Canada or elsewhere in environmental samples. Judging from concentrations which have been reported to date, it appears that the mono- and di-methyltin, butyltin and octyltin species pose no threat to aquatic organisms in Canada vis-à-vis acute toxicity. Data on the persistence of these species in aquatic environments are in some cases fragmentary or non-existent, but in general it appears that these species would not be persistent in aquatic environments, with half-lives estimated to be less than a few months at 20°C.
A Review of Approaches to Achieve Low Effluent Phosphorus Concentrations
Authors: Nutt Stephen G.
Published: March 2019

Total phosphorus (TP) concentration limits substantially lower than currently imposed on municipal WPCP effluents may need to be achieved in specific areas of Ontario to protect water quality. The capability to achieve low effluent TP levels (<0.20 mg/L) on a consistent basis has not been widely demonstrated in Ontario. To determine the feasibility of achieving the concentration limits being considered, a review of the capabilities of proven and innovative technologies was undertaken.

As a result of this review, it was recommended that: (i) full-scale demonstration tests of the capability of post-precipitation plus filtration to achieve effluent TP levels less than 0.1 mg/L should be undertaken at several selected Ontario WPCPs; (ii) full-scale testing of multiple-point chemical precipitation operating options (i.e. pre-precipitation plus simulation precipitation, pre-precipitation plus post-precipitation, etc.) should be undertaken at selected Ontario WPCPs to define the capabilities and benefits associated with the various operational modes; (iii) the cost and effectiveness of post-precipitation in conjunction with tertiary filters should be compared to that of post-precipitation in conjunction with tertiary solids contact flocculator clarifiers and post-precipitation in conjunction with filters and solids contact clarifiers to determine the most appropriate process train for meeting low effluent TP limits; (iv) the cost and effectiveness of activated alumina for polishing municipal treatment plant effluents to TP concentrations below 0.1 mg/L should be compared to that of conventional chemical post-precipitation processes; and, (v) the potential impacts of high chemical dosages on the sludge management processes (digestion and land utilization) and on effluent toxicity should be evaluated.
Destruction of Pollutants and Microorganisms in Water by UV Light and Hydrogen Peroxide
Authors: Sundstrom D.W. , Weir B.A. , Barber T. A. , Klei H. E.
Published: March 2019

This project investigated the destruction of organic compounds and microorganisms in water by ultraviolet catalyzed oxidation using hydrogen peroxide as the oxidizing agent. The combination of UV light and hydrogen peroxide was effective in decomposing all of the organic compounds studied. The rates of destruction increased with increasing peroxide concentration and UV light intensity, and were highly dependent on chemical structure. The destruction of mixtures of organic compounds showed strong interactions between reacting components. The inactivation of E. coli and B. subtilis spores by UV light and/or hydrogen peroxide was studied in flat plate reactors. By using thin liquid films, the combination of UV light and peroxide greatly increased the rates of inactivation of both microorganisms. The results were correlated by a mixed second order kinetic model.
Degradation of Nitrobenzene and Nitrophenols in Homogeneous Aqueous Solution
Authors: Lipczynska-Kochany Ewa
Published: March 2019

Degradation reactions of aqueous nitrobenzene (1), 2-nitrophenol (2), and 2,4-dinitrophenol (3) by means of the photolysis in the presence of the Fenton reagent (FeCL2/H2O2) (I) were investigated. The results were compared with those for 4-nitrophenol (4) as well as for direct photolysis (II), the photolysis in the presence of hydrogen peroxide (III) and the dark Fenton reaction (IV) of (1)–(3), reported elsewhere. In all the cases, decomposition of the aromatic nitrocompounds was observed. The best results were obtained when the solutions of nitrophenols 2–4, containing the Fenton reagent, were irradiated with the polychromic UV light. The rates of the compounds 1–4 degradation depend on their electronic structures in the ground and excited states. The mechanisms of the degradation of 1–4 by means of direct photolysis, the Fenton reaction, the photochemical reactions in the presence of hydrogen peroxide and the Fenton reaction are discussed. The developed method I is concluded to be more effective than II–IV, and therefore recommended for the elimination of the compounds 1–4 from waters and wastewaters.
Sustainable Management of Urban Lakes: A New Environmental Challenge
Authors: Barica J.
Published: March 2019

In view of the exponential growth of human population in urban areas during the last century, more attention should be paid to large city ecosystems as specific ecological bioregions. There is a need to shift the present biocentric-naturalist views prevailing in environmental circles to include the human population as an integral part of the ecosystem in a stringent application of the principles of the ecosystem approach and sustainable development. A new environmental realism is needed: boundaries and limits of ecological sustainability have to be respected and necessary caps imposed through rational urban planning and settlement policies. The urban lakes can serve as living indicators of good environmental management or mismanagement, as well as overall urban environmental health.
Evidence of Recent Eutrophication of an Urban Lake in Nanjing, China
Authors: Dickman M. D.
Published: March 2019

There is very little known about urban lakes in China, and for this reason this paper provides a synthesis of palaeolimnological and past and present phytoplankton studies of Xuanwu Lake, an urban lake near the center of Nanjing, in Jiangsu Province, China.

Documented changes in biotic species diversity and water chemistry in this urban lake over the last thirty years have been attributed to progressive eutrophication associated with lake in-filling, commercial harvesting of plants and fish and intense industrial and urban activities within the lake's watershed. During the last decade, phytoplankton biomass in Xuanwu Lake has increased ten fold. This has resulted in a steady shallowing of the lake's photic zone to a depth of less than 0.7 m with Secchi transparencies of 0.3 to 0.4 m.

Wind-generated currents prevent anoxia from occurring in this shallow wind-swept lake no matter how eutrophic the lake. As a result, many of the negative impacts of hypertrophication, such as anoxia, fish kills and noxious odors, are avoided. Thus, shallow lakes like Xuanwu Lake can become eutrophic without producing long periods of hypolimnetic anoxia such as those frequently reported for deeper eutrophic lakes. It was concluded that it is important to treat deep urban lakes differently from shallow urban lakes as the latter systems rarely display extended periods of anoxia, fish kills and noxious odors.
Artificial Marshes to Maintain Water Quality: The Beach of Ile Notre-Dame, Montréal
Authors: Vincent Gilles
Published: March 2019

In June 1990, the City of Montréal opened a beach on an artificial lake in the southern sector of Ile Notre-Dame in the Saint Lawrence River, a man-made island built for Expo ’67. This lake is fed from the Saint Lawrence River and the beach stretches some 600m with a swimming area of approximately 15 000 m2. Since the desired environmental character was that of a natural lake, it was decided to avoid the use of conventional methods of water purification such as treatment with chlorine. Instead, a series of techniques more compatible with natural systems were chosen in order to maintain water quality. The major component of these techniques is a “filter-lake” complex. Occupying an area of 20 000 m2, the “filter-lake” complex consists of four ponds of varying depth where more than 100 000 aquatic plants of different native species were introduced. Intake pipes draw 28 litres/second of water into the first pond and then, water circulates by gravity through the three remaining ponds. During the last two seasons, several parameters were monitored in order to evaluate the efficiency of the system. The parameters considered were: soluble reactive phosphorous, total phosphorus, dissolved phosphorus, nitrates, ammonium, suspended solids and faecal coliforms. Preliminary results indicate that the system of artificial wetlands used at the beach of Ile Notre-Dame is efficient in water purification. The ponds are very good traps for soluble reactive phosphorus and nitrates. A good interception is also observed in the second pond for total phosphorus and suspended solids. Faecal coliforms removal however seems uncertain and long-term effectiveness is questionnable.
Management Strategies for Eutrophication and Macrophyte Growth in Two Urban Lakes in Saint-Bruno, Quebec
Authors: Leduc Roland , Anderson M. Robin
Published: March 2019

Two small, shallow lakes (Ruisseau and Village lakes), located in Saint-Bruno near Montreal (Québec), were studied in 1987 to determine the extent of, and to propose alleviation solutions to eutrophication and to macrophyte growth. Flows and various water quality parameters were monitored in the influents and in the lakes, and macrophytes were harvested at four different locations in Village Lake. Both lakes were found to be highly eutrophic. The dominant plant specie was found to be Myriophyllum spicatum. Biomass densities were high with values of 206, 212 and 395 g/m2 at three of these sampling locations. A number of alternatives which could mitigate eutrophication and the presence of macrophytes are discussed in terms of technical feasibility and cost. Source control of nutrients, along with citizens involvement, and partial control of macrophytes were recommended management strategies.
Reproductive Dysfunction and MFO Activity in Three Species of Fish Exposed to Bleached Kraft Mill Effluent at Jackfish Bay, Lake Superior
Authors: Munkittrick K.R. , Van Der Kraak G.J. , McMaster M.E. , Portt C.B.
Published: March 2019

Our recent studies have demonstrated reproductive dysfunction in white sucker (Catostomus commersoni), longnose sucker (C. catostomus) and lake whitefish (Coregonus clupeaformis) populations exposed to bleached kraft mill effluent (BKME). Although all three species show elevated levels of hepatic mixed function oxygenase (MFO) activity and depressed circulating steroid levels, we have been unable to provide clear evidence of whether these two events are directly linked to whole organism changes. Although depressed steroid levels appear to be linked to delayed sexual maturity, changes in fecundity and reduced secondary sexual characteristics in white sucker and lake whitefish, longnose sucker show no impacts of reduced steroid levels on reproductive performance. Installation of secondary treatment at this pulp mill did not alleviate the steroidal dysfunction or MFO induction. However, samples collected after a two week maintenance shutdown showed a return to reference levels of MFO activity in both sexes and of steroid levels in male fish. The relationship between elevated MFO activity and depressed steroid levels is unclear, but detailed experiments suggest that the two phenomena are not directly linked. White sucker show depressed steroid production and impaired reproductive regulation independent of MFO activity.
Chlorate Discharges from Pulp Mills: An Examination of Effects on River Algal Communities
Authors: Perrin C. J. , Bothwell M. L.
Published: March 2019

To avoid the formation of organochlorine compounds in pulp products and effluents discharged into the environment, there is a trend in the North American pulping industry to change from molecular chlorine to chlorine dioxide bleaching. However, chlorate (ClO3−) formed during chlorine dioxide bleaching is known to have toxic effects in some marine algae and has been implicated in environmental problems in the Baltic Sea. This study examined the potential effects of chlorate on natural freshwater, riverine diatom communities characteristic of many rivers in western Canada. Under low ambient river nitrate concentrations (ca. 10 µg•L−1 NO3−N), chlorate additions of up to 500 µg•L1 ClO3 did not reduce the specific growth rates (µ) or change the taxonomic composition of the attached riverine diatom community. The lack of chlorate toxicity to freshwater diatoms suggests that the nitrate uptake and/or reduction mechanism(s) of freshwater diatoms have much higher affinities for NO3 than ClO3 compared to many marine macroalgae. These results indicate that chlorate discharged from new or upgraded pulpmills into freshwater river environments will not cause environmental changes to the dominant algal producers such as diatoms.
Modelling the Fate of Organochlorine Chemicals in Pulp Mill Effluents
Authors: Mackay Donald , Southwood Jeannette M.
Published: March 2019

A comprehensive and flexible water quality model is described which can be used to evaluate the fate of chemicals discharged from an industrial source, such as a pulp mill, into a multi-compartment receiving environment consisting of three water columns exposed to the atmosphere, each with a sediment compartment, and five classes of organisms exposed to chemicals present in water and sediment. The aim of the model is to provide a method by which known loadings of organochlorines and other chemicals from a specific mill can be used, along with other input information (e.g., inputs from other mills, advective inflow from nearby waters, and from atmospheric deposition) to deduce amounts and concentrations of chemicals and process rates (e.g., rates of evaporation or transformation) in water, sediments and biota.

Results are presented for an evaluative system and for a trichlorophenol and a trichloroguaiacol in a real system in Northern Ontario. Discrepancies found between observed and calculated concentrations of the trichlorophenol and the trichloroguaiacol in the receiving environment are discussed. Recommendations are made for studies which will elucidate the causes.