bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of Indigenous Enteric Viruses in Raw Sewage Effluents of the City of Athens, Greece, During a Two Year Survey
Authors: Krikelis V. , Markoulatos P. , Spyrou N. , Serie Ch
Published: May 2018

In a two year survey of enteric viruses in urban sewage effluents of Athens, Greece, during 1982–1983, indigenous Enteroviruses and Adenoviruses have been detected. Enteroviruses, (Polio, Coxsackie B and Echo) were recovered on Vero or BGM cells by inoculation of samples, after a pre-concentration step utilizing glass powder. Adenoviruses were recovered on Hep2 cells after being Precipitated with protamine sulfate. The viral content was in the order of 102 -103 cytopathogenic units (CPU) per litre of sample. Seasonal fluctuations of the various serotypes recovered were observed. The peak of Adenoviruses was found in early spring whereas Enteroviruses peaked in late summer-early fall. The most frequently recovered serotypes within each group were : Polio III (47%), Coxsackie B5 (56%), Echo 7 (61%) and Adeno 7 (43%). Similar isolation frequencies, except for Polio, were found in humans as well. As regards Polioviruses, all strains recovered from sewage were found to be vaccine-related by the intratypic serodifferentiation test.
Examination of the Penetration of Enteric Viruses in Soils under Simulated Conditions in the Laboratory
Authors: Jørgensen P. H.
Published: May 2018

In two different unsaturated soil columns percolated with artificial rainwater under simulated aerated conditions, transport of coxsackievirus B3 and adenovirus 1 below 3.5 cm under the soil surface could not be demonstrated. The viruses were applied to the columns as seeded sewage sludge. Under saturated conditions transport of water-suspended coxsackievirus B3 was faster in a soil column with sandy loam soil than in a diluvial sand column.
Thermophilic Anaerobic Contact Digestion of Palm Oil Mill Effluent
Authors: Ibrahim A. , Yeoh B. G. , Cheah S. C. , Ma A. N. , Ahmad S. , Chew T. Y. , Raj R. , Wahid M J. A.
Published: May 2018

The palm oil industry is one of the major agro-based industries in Malaysia whose production accounts for more than 90% of the world export. The industry, however, also generates enormous quantities of liquid waste with high organic load causing serious pollution problems. In view of the high level of organics, anaerobic pretreatment is usually practised prior to aerobic breakdown. Most of the anaerobic digesters installed at the mills are currently operated under mesophilic conditions. However, the inherently high temperature of the effluent suggests that thermophilic digestion would bring about a much more effective system. This paper reports on results obtained from a pilot plant study on thermophilic anaerobic contact digestion of palm oil mill effluent which has been conducted and includes a microbiological study associated with the investigation.
Disinfection of Drinking Water Rich in Bromide with Chlorine and Chlorine Dioxide, While Minimizing the Formation of Undesirable By-Products
Authors: Rav-Acha Ch. , Serri A. , (Goldstein) Choshen E. , Limoni B.
Published: May 2018

Although chlorine dioxide does not form trihalomethanes (THM) and produces very few non-volatile haloorganic materials in drinking water, intensive investigations bearing on the formation of chlorite by ClO2 disinfection reveal that the rate of chlorite formation reflects the rate of ClO2 consumption and as long as the amount of ClO2 applied is behind its demand, about 60% of the chlorine dioxide consumed is converted into chlorite.

Mixtures of Cl2 and ClO2, which may successfully reduce the formation of haloorganic compounds, as well as of chlorite in the absence of bromide, fail to do this where water rich in bromide is concerned. As a result of bromide oxidation by chlorine, bromine is formed, which in turn reacts more intensively with organics than does chlorine and thus favours the formation of THM and other halogenated organic materials.

This problem can, however, be circumvented if ClO2 is allowed to react in water with the organic precursors before chlorine is introduced. A pre-treatment with 1 ppm of ClO2 two hours before the application of 2 ppm Cl2, was found to reduce the formation of THM by 60% relative to its formation by chlorine alone, and the chlorite is reduced in this case by up to 90% relative to its formation by chlorine dioxide alone.

This is of particular importance since it can solve some of the major problems bearing on the impact of disinfection upon the formation of undesirable by-products.
Inactivation of Hepatitis A Virus, Other Enteric Viruses and Indicator Organisms in Water by Chlorination
Authors: Grabow W O. K. , Coubrough P. , Hilner C. , Bateman B. W.
Published: May 2018

Hepatitis A virus (HAV) and various indicator organisms were mixed together in autoclaved biofilter effluent and broth-enriched tap water, and the survival kinetics of individual organisms after the addition of chlorine were compared. Chlorine was present in the reaction mixtures predominantly in the form of combined residuals. HAV was enumerated by a most probable number dilution assay using PLC/PRF/5 liver cells for propagation of the virus and radioimmunoassay for its detection. In both reaction mixtures HAV survived longer than Escherichia coli, Streptococcus faecalisi, poliovirus type 2, coxsackievirus B5 and reovirus type 3, while it was less resistant than coliphage MS2, coliphage VI (except in tap water), the simian SA-11 rotavirus and Mycobacterium fortuitum. The survival data indicate that viruses (including coliphages) tend to be relatively more resistant to combined chlorine residuals than bacteria, while bacteria tend to be relatively more resistant to free chlorine residuals than viruses. Coliform bacteria may thus be fairly reliable indicators of the virological safety of waters disinfected by free chlorine residuals, but not of waters disinfected by combined chlorine residuals, as in the case of the chlorination of wastewater or the chloramination of drinking-water supplies. The relatively high resistance to combined chlorine residuals of HAV and SA-11 virus (which is closely related to human rotavirus) emphasizes the shortcomings of methods available for virological water analysis because they do not detect HAV and rotavirus. The results support views that the virological safety of all chlorinated waters can be reliably monitored by means of practical indicator systems consisting of appropriate combinations of determinands such as the standard plate count, coliform bacteria, coliphages, acid-fast bacteria and faecal streptococci.
A Potential Treatment Alternative for Swine Wastewater in the Tropics
Authors: Yang P. Y. , Nagano S. Y.
Published: May 2018

Development of a low-cost and effective swine waste management system in the tropics is the main objective of this study. Because of the apppropriate temperature environment and abundance of sunlight, an integration of an anaerobic digestion and an algal biomass process was selected and investigated. A pilot, plant integrating a 20 m3 anaerobic digester with sludge recycling and a 120 m3 algal-biomass raceway were installed and evaluated. Maximum gas production rate of 1.527 liter/liter/day (69% methane content) can be achieved by a TVS loading rate of 4.23 gram/liter/day. A sludge production rate of 0.82-2.62 g TS/liter is obtained from a TVS loading rate of 0.76-4.23 g TVS/liter/day. Critical SRT for maximum gas production rate is 2.67. For the algal biomass raceway, a loading rate of 0.097 g SCOD/liter/day or 0.017 g NH4-N/liter/day would achieve SCOD and NH4-N removal efficiencies of 94.44% and 98.42%, respectively. Combining the previous analysis of energy input and land requirement for an algal biomass raceway and mass balance of energy production and utilization, integrating the energy production (anaerobic digestion) and energy utilization (dehydration of digested sludge and power requirement of raceway) provides a great potential for a swine wastewater treatment in the tropics.
Continuous, Automatic Detection of Organophosphates and Carbamates in Water Utilizing Enzyme Microcalorimetry
Authors: Morgan W S. G. , Kühn P. C. , van Niekerk P. P.
Published: May 2018

An enzyme calorimetric method, employing immobilized cholinesterase to detect harmful levels of organophosphorus and carbamate insecticides in water, is described.

Immobilized cholinesterase activity was assessed automatically in a microcalorimeter by analyzing its catalytic efficiency in hydrolyzing a substrate solution which was passed over the enzyme at regular time intervals. A microcomputer was used to automate the procedure and for data acquisition.

The inhibitory effects of three organophosphorus and two carbamate pesticides upon cholinesterase were studied in order to evaluate the efficacy of the technique.
Management of Urban Waste Water Physico-Chemical Treatment Stations: Servocontrol of Reagent Additions at the Quiberon Sewage Treatment Plant, France
Authors: Marchandise P. , Legendre J. P. , Delacroix D. , Rivoal J. L.
Published: May 2018

The physico-chemical treatment of sewage requires the addition of costly reagents. The quantities added are generally proportional to the flowrate treated. Recent progress in pollution detectors now makes it possible to measure sewage concentration continuously. This makes it possible to match the quantity of reagent added to the treated-water quality objective set. COD-SM-Turbidity relations have been determined at various sites. An assessment of the performance of a servocontrol device during the summer of 1983 is presented.
Hexavalent Chromium Removal from Drinking Water
Authors: Philipot J. M. , Chaffange F. , Sibony J.
Published: May 2018

A series of tests were performed with a view to solving the problem of chromium pollution in the Meulan district near Paris, due to the proximity of long-established metal-working plants. It was found that the accumulated pollution not only originated from the groundwater source but also from atmospheric contamination through fall-out from smoke and fumes issuing from local metal-works' stacks. Among the interesting features of this paper is the fact that, since the profound penetration by the pollutant affects potable feedstock, chromium removal studies have been made on potable water for the first time on record.

Several methods are reviewed, among which the only economically feasible one appears to be the reduction of hexavalent chromium by a sufficient quantity of iron sulphate, the problem attached to iron-sulphate overdose being solved by the application of high-rate filtration on very fine sand. This arrests the fine precipitates and reduces the residual ferrous-iron by catalysis. Reliability of the treatment is ensured by a system of continuous metering that automatically controls reagent dosing.
The Problem of Phosphorus in France – Its Presence in Natural Waters and Biological Phosphorus Removal
Authors: Vinçonneau J. C. , Schaack F. , Boschet A. F. , Chevalier D. , Villesot D. , Jaubert M. , Laval Ch , Lambert S.
Published: May 2018

The problem of nutrient inputs to surface waters is reviewed. These inputs lead to eutrophication and an undesirable decrease in water quality. The origin and effects of eutrophication, and the principles of its control are described. The preferred method of control is through the reduction of phosphorus inputs. The origins of phosphorus inputs and methods of limiting these are considered, in particular through physico-chemical and biological treatment processes in sewage treatment plants. It is concluded that efficient control of eutrophication through reduction of phosphorus inputs is possible.
Polyphosphate Kinase Activity during Phosphate Uptake by Bacteria
Authors: T'Seyen J. , Malnou D. , Block J. C. , Faup G.
Published: May 2018

Polyphosphate kinase, one of the key enzymes for polyphosphate accumulation in bacteria, has been investigated in pure culture and activated sludge samples. Three bacterial species (Acinetobacter lwoffi, A. phosphadevorus and Pseudomonas fluorescens) appeared to have a polyphosphate kinase activity (between 0.3 and 4.7 nM of P04 transferred per minute and per mg of proteins). However tests carried out on Aeromonas hydrophila, Bacillus subtilis, E. coli and Serratia sp. showed these species did not have any measurable polyphosphate kinase activity.

Enzyme activity in bacteria is dependent on environmental conditions and can be induced, in particular, by anaerobic stress, even without modification of extracellular phosphate concentrations. Most of the activated sludge samples taken from laboratory pilot plants achieving good phosphorus removal did not present any measurable polyphosphate kinase activity. Such poor results can be related to low numbers of phosphorus removing bacteria and inhibitory molecules in sludge extracts. The only observed activity was in pretreated sludges (washed sludges) and in sludges submitted in a batch reator to phosphate starvation. However, in these, enzyme activity was at least 20 times lower than those measured in pure culture of A. lwoffi.

Polyphosphate kinase induction is a complicated and time consuming method which has to be used only in the research field. At the present time our results show that sludge phosphate uptake potential cannot be predicted by the measure of induction of polyphosphate kinase activity.
Design Strategies for Nutrient Removal Plant
Authors: Barnard James L. , Stevens Gerry M. , Leslie Patrick J.
Published: May 2018

The first full-scale Bardenpho plant in the colder regions of North America was constructed in Kelowna and operated for about two years. The design was based on criteria developed by Barnard (1974) and based on experience of the design of similar plants in South Africa. Maximum flexibility leaving the operator many options for optimization was allowed. Effluent ortho-phosphate, nitrate and ammonia concentration averaged 0.43, 2.05 and 0.78 mg/ℓ respectively over the first year of operation. Operating results are compared with design predictions. Some results are presented and the design was tested using theories developed by Ekama et al (1984) whose models predicted that no phosphate removal would be possible.

RESUME

La premierè installation de Bardenpho, à grande échelle dans les régions les plus froides de l'Amérique du Nord a été construite à Kelowna et utilisée pendant plus de deux ans. Le dessin était fondé sur les information de Barnard (1974) et basé sur l'expérience du dessin d'installation sembables en Afrique du Sud. L'installation était flexible et laissait à l'opérateur le choix de plusieurs options pour l'optimisation. La concentration de ortho-phosphate, nitrate et ammoniaque avait les valeurs moyennes de 0,43; 2,05 et 0,78 mg/ℓ respectivement pendant la premiére année de travail. Les resultats sont presentés et la dessin a été mis à l'épreuve en utilisant les théories développées par Ekama et al (1984) dont les modèles ont predit. qu' aucun élimination de phosphate serait possible vu le petit réduction de nitrate qui le modèle ont prédit aux températures plus froides.
Pilot Scale Studies on Enhanced Phosphorus Removal in a Single-Stage Activated Sludge Treatment Plant
Authors: Maier W. , Kainrath P. , Krauth Kh , Wagner R.
Published: May 2018

Enhanced biological phosphorus removal from domestic sewage was investigated in a single-stage activated sludge treatment plant with pre-denitrification operated in a continuous process. In 10 different experimental periods the influence of varying composition of the influent, varying systems of the pilot scale unit (with and without anaerobic basin), varying retention times in the different basins and varying sludge loads were investigated. Results of the experiments can be summarized as follows: the nutrient situation and especially the P/BOD5 and N/BOD5 ratios, retention time in the final clarifier, and organic sludge load plus the desired degree of nitrification have essential influence on the process and P removal efficiency. The conclusions for the pilot scale process are discussed.
Water Treatment by Means of Activated Carbon, Prepared from Locally Available Waste Materials (II)
Authors: Keirsse H. , Van Hoof F. , Janssens J. , Buekens A.
Published: May 2018

Man's natural water supplies are threatened by a large number of nonbiodegradable and toxic organic compounds. Proper environmental standards often can only be attained using tertiary treatment processes, such as adsorption on activated carbon. The latter is an expensive process, owing to the initial cost of activated carbon and the losses occurring during regeneration. Methods are being investigated at the Free University of Brussels for producing and activating carbon, using various types of waste as a raw material.

Following materials have already been used : cacao hulls, sawdust, fruit stones, bark, and waste tyres. Both carbonization and activation have been conducted under the carefully controlled conditions of a fluidized bed reactor. The influence of the following process parameters has been investigated : pyrolysis temperature and time, activation temperature and time, and composition of the furnace atmosphere. The resulting activated carbons should exhibit the following qualities : high adsorption capacity and rate, good resistance to attrition, and possibility of regenerating the carbon. The properties of the carbon obtained have been evaluated by means of a number of standard tests (Iodine-index, BET-surface, Tannin-index, Methylene blue-index, and Phenol-index), and adsorption isotherms of phenol, pentachlorophenol, p. toluene sulphonate and dodecyl benzenesulphonate. In general the properties of the carbons obtained were comparable to those of commercial qualities.

Some of the activated carbons tested will soon be evaluated using synthetic and real phenolic industrial wastewaters (1.5 % of phenol).
Acid Neutralizing Capacity of Glacial Sediments in Western Ungava
Authors: Wilson H. , Bouchard M. A. , Delisle C. E.
Published: May 2018

The present research evaluates the sensitivity of the terrestrial and aquatic ecosystems to acid precipitation in western Ungava, Quebec. PH values of the acid-sediment mixtures were used to classify the sediments according to their capacity to neutralize acid. The carbonate and the silt and clay content of the sediments are considered as the main controlling factors of their neutralization properties. Average acid neutralizing capacity (ANC) values were calculated for 14 sites. PH values, determined from the neutralization characteristics at each site, were used to classify the sites on a pH scale, presumably a sensitivity scale. On this scale, the least sensitive site, with pH remaining above 7, is from the coast of Hudson Strait where the sediment is a clayey fossiliferous glaciomarine diamicton. Of higher but still relatively low sensitivity, with pH remaining above 4.5, are two sites below the Tyrrell Sea marine limit, where the sediments are predominantly shell-bearing raised littoral deposits. Of high sensitivity, with pH below 4.5, are the remaining sites either below or above marine limit. Those below the marine limit have sediments mostly devoid of shell material. Those above the marine limit have till as the predominant type of sediment. By comparison to pH values determined for samples collected further south, namely in the Chibougamau-Lac Mistassini region, in the Thetford Mines region, and in northeastern Ontario, the group of samples with pH remaining above 7 may be qualified as showiny low sensitivity, those with pH between 7 and 4.5, of intermediate sensitivity, and finally those with pH below 4.5 of high sensitivity. It is concluded that ANC determinations can provide an adequate means of quantitative comparisons between widely separated regions and could possibly be used as one index of terrain sensitivity. Full assessment of terrestrial sensitivity to acid precipitation must also consider the hydrogeological characteristics at different localities. For instance, in those parts of Ungava where the permafrost table is near the surface, the saturation of the thawed upper layer prevents significant infiltration thereby limiting the possibility of neutralizing acid rain, regardless of the ANC characteristics of the sediments.
Atmospheric Environment Service Long Range Transport of Air Pollutant Activities in the Territories
Authors: Thomson R. B.
Published: May 2018

Acid deposition monitoring and modelling in the Northwest Territories and Yukon Territories are reviewed. Data gathered since 1974 indicate that sulphur in precipitation is less than 1 kg/ha/yr. Trajectory calculations using numerical models are discussed that demonstrate a pattern of northeastward transport of pollutants from Alberta into southern sections of the Northwest Territories.
Refuse, Recycling and Resource Recovery in Industrial Applications
Authors: Law I. B.
Published: May 2018

Growing environmental pressures and escalating intake water costs are causing an increasing number of industrialists to reappraise their effluent treatment facilities with a view to effluent recycle and/or resource recovery. In certain instances industrialists have opted for treated sewage effluent as a water source for their process. Water Management Schemes are being, or have been, implemented at a number of industrial concerns in order to rationalise overall water intake and effluent disposal costs.
A Low Cost Method for Nutrient Removal from Domestic Wastewaters
Authors: Ignjatovic L. , Marjanović P.
Published: May 2018

At the town of Sokobanja, experiments were conducted with selected aquatic macrophytes in order to remove nutrients from domestic wastewater and thus improve the effluent quality and help prevent the eutrophication of lake Bovan. The effective use of Eichornia crassipes Martius (water hyacinith), Pistia stratiotes I. (water lettuce) and Salvinia auriculata for the removal of BOD, NH3 and PO4 has been demonstrated. In the course of the experiments temperature proved to be the most significant limiting factor under local conditions. The plants are of tropical origin which makes them very suitable for use in Mediterranean countries. A special advantage of this technology also lies in the fact that the plants cannot survive in braekish water and there is no danger of their propagation into marine ecosystems. The technology can be implemented very efficiently by slightly adapting the existing stabilization ponds or by constructing new specialized systems. In any case, the economic effects can be extremely positive since there is no need for expensive equipment and skilled labour.
Combined Microbiological and Advanced Treatment of Oil Refinery and Municipal Wastewaters
Authors: Dalmacija B. , Miskovic D. , Zivanov Z. , Petrovic O.
Published: May 2018

A study has been done of the primary microbiolooical purification of mixed oil refinery and municipal wastewater using the active sludge process in a two-stage laboratory set-up. The advanced - secondary microbiological treatment of the mixed wastewaters was accomplished by using biologically active carbon. The highest total effect of the organic matter removal for both the primary and secondary microbiological treatment was achieved when the two wastewaters were mixed in the ratio 1:1, and it ranged from 97.7 to 99.2 %, The organic matter load in the effluent expressed as BOD5, was 0.3 - 5.7 mg O2/dm3. When conditions in the columns containing biologically active carbon were changed from aerobic into anaerobic ones, the denitrification bacteria were allowed to use the adsorbed organic matter as the substrate. In this way, the achieved nitrate removal was up to 72 %. It was found that active carbon had adsorbed the organic matter 1.37 - 2.10 times more than was its adsorption capacity, while the free surface degree was in the ranoe of 44.5 - 59.7 %. On the basis of the obtained results, the kinetic coefficients were calculated for both the primary and secondary microbiological treatment of the mixture of the oil refinery and municipal wastewaters. Finally, two alternatives of the technological procedure were proposed for such treatment.
The Self-Purification Capability of Karst Underground Watercourses with Respect to the Pollution of the Mediterranean Sea
Authors: Preka N. , Preka-Lipold N. , Avdagic I. , Kurpjel B.
Published: May 2018

This paper has reviewed the results of the organic selfpurification process that occurs in karst underground watercourses. The investigations were carried out in two test reaches between 1974 and 1984.

The first reach comprised the underground section of a river in an area of shallow karst in Slovenia, while the second one was in the deep karst area of Eastern Herzegovina.

The fundamental studies of the change in the BOD loadings showed the value of the oxygen consumption rate coefficient in karst groundwaters, transferred to a temperature of 20° C, to be k1 (r) = 0.160 to 0.210. To determine the change in loadings, the Upstream - downstream method was applied, while the travel time was defined by using a tracer. An identical value of the deoxygenation coefficient was found when observing the changes in the daily loads at the exit profile only. This knowledge enables the practical application of coefficient k1 to estimate the input organic load in karst catchment areas, and also to define the required level of karst springs and coastal sea protection.
From Coastal Water Pollution Control to the Reclamation of Sewage
Authors: Degaetano J. C. , Mallia H. J.
Published: May 2018

Following Master Plan studies by the World Health Organisation and other consultant sanitary engineers on wastes disposal, the Maltese Government implemented in successive stages projects aimed at the abatement of the pollution of bays and seaside resorts around the island, culminating in the laying of a submarine outfall to discharge some 90 % of the sewage produced on the island. After thus cleaning the blue coastal waters, sewage has been reclaimed for the beneficial use by the farming community. This case study describes three projects carried out in order to achieve the aims stated.
Effect of Sunlight on Coliphages in an Oxidation Pond
Authors: Ohgaki Shinichiro , Ketratanakul Awrapin , Prasertsom Uthaiphun
Published: May 2018

Escherichia coli B were used as host cells for isolation and multiplication of coliphages. The coliphages were isolated from a small canal which receives the effluent from an oxidation pond in Bangkok, Thailand, and were used as a virological indicator. Coliphages were assayed by the plaque forming technique (PFU method). The coliphage which was used in this study had no resistance to acid (pH3) and weak resistance to alkali (pH 10).The fate of coliphages in the oxidation pond was investigated by field measurement and laboratory experiments.

Batch experiments showed the adsorption of coliphage to microbial particulates (mainly algae) occurred under aerobic conditions. The desorption of coliphage from the particulates was observed under anaerobic conditions. The adsorption-desorption process was reversible and was controlled by dissolved oxygen concentration. The same mechanism of adsorption-desorption was observed in the oxidation pond as well. During day-time, the concentration of coliphage decreased under high concentration of dissolved oxygen caused by photosynthesis. On the other hand, the concentration of coliphage increased after sunset because the dissolved oxygen concentration in the pond decreased to zero due to respiration of algae.

The degree of removal of coliphage in the oxidation pond (design retention time = 20 days) was 90% (1 log). Field measurement with submerged bottles in the oxidation pond and sunlight-exposure experiment using beakers showed that coliphage could be inactivated by sunlight only near the water surface (less than 10 cm depth, the highest estimate) in the oxidation pond.
Comparative Disinfection of Indicator Bacteria and Poliovirus by Chlorine Dioxide
Authors: Fujioka R. S. , Dow M. A. , Yoneyama B. S.
Published: May 2018

The effectiveness of ClO2 to disinfect poliovirus and indicator bacteria in clean water and sewage was determined. Clostridiumperfringens was the most resistant to disinfection by ClO2, followed by poliovirus, s. faecalis (fecal streptococcus) and E. coli (fecal coliform). These results suggest that reduction in concentrations of C. perfringens. but not fecal coliform or fecal streptococcus, can be used as a simple monitoring assay to determine if ClO2 treatment conditions to disinfect human enteric viruses had been achieved. In sewage effluent a small and variable fraction of fecal coliform and fecal streptococcus were highly resistant to disinfection by ClO2 and often persisted longer than the measurable levels of poliovirus. This resistant fraction of indicator bacteria was determined to be associated with particulate matter which protected the bacteria from disinfection.
Drinking Water Transmission of Giardiasis in the United States
Authors: Akin E. W. , Jakubowski W.
Published: May 2018

For about a century after Giardia was named by Lambl in 1859, the occurrence of the organism in humans was not widely considered significant in explaining the etiology of disease. This organism is now recognized as a cause of disease that ranges from mild to severe and debilitating gastroenteritis. Beginning in 1965, drinking water became increasingly implicated as an important route of transmission. An outbreak occurred in a Colorado ski resort in that year. A survey of visitors to the resort revealed that 123 persons experienced acute enteritis, possibly giardiasis. Sewage contamination of the well water supply was thought to be the source of the organism.

Further evidence for waterborne transmission of Giardia came in 1975 with the first isolation of the organism from a water supply implicated in an outbreak. A cyst was isolated from the water supply during an extended outbreak that resulted in 359 confirmed cases over a 7 month period. Subsequent outbreaks have clearly established the role of water in Giardia transmission. From 1965 through 1984, 90 waterborne outbreaks with 23 776 cases of giardiasis were reported in the United States. This report discusses the etiologic agent and examines drinking water outbreak occurrence and control.
Milliscreening: A Pretreatment Option for Marine Disposal
Authors: Bannatyne A. N. , Speir J.
Published: May 2018

The Hutt Valley Drainage Board Milliscreen Treatment Plant, commissioned in July 1984, treats municipal waste using 0.5mm and 1.0mm wedgewire single pass rotary screens. The plant is designed to remove all gross solids not readily assimilated by the sea and is an alternative to primary treatment prior to discharge into coastal waters via a marine outfall. This paper describes the plant and background to the investigations, pilot plant studies, design, and operational data available to date. Milliscreening as a pretreatment option for marine disposal is also discussed.
Modelling Toxic Response of Anaerobic Treatment
Authors: Speece R. E. , Parkin G. F. , Bhattacharya S. K.
Published: May 2018

The toxicity response of the anaerobic treatment process can be modelled from a number of different approaches. Toxicity affects the growth rate and the effluent substrate concentration and can be modelled by competitive and uncompetitive inhibition. The biological safety factor is reduced. Most toxicants exhibit reversible toxicity, which is quite significant. Acclimation is noted to some toxicants. Molecular structure can be used to model and predict toxicity.
A Strategy for Design of Marine Pollution Monitoring Studies
Authors: Segar D. A. , Stamman E.
Published: May 2018

Most historical marine pollution monitoring has proven useless in a management context. A strategy for development of effective marine pollution monitoring programs is outlined. This strategy is based on the following steps: 1) systematic evaluation of the management information needs, 2) identification of the hypothetical impacts associated with those management concerns, and 3) investigation of the feasibility of monitoring those effects such that the existence, or absence, of a specified level of effects can be established in a statistically-valid manner. There are two fundamentally different types of monitoring program: site-specific and regional. These two types of program differ markedly in scope and approach when designed through application of this strategy. The strategy requires development of null hypotheses which address management concerns and which are amenable to scientific testing. In order for the program to be successful, the null hypotheses selected for inclusion in a marine pollution monitoring program must address levels of effect which are predefined to be environmentally significant. The definition of environmentally significant effect levels is a difficult process which must be primarily the responsibility of the managerial community.
Investigation of Material Transport and Load in Tidal Rivers
Authors: Fanger H.-U. , Kuhn H. , Michaelis W. , Müller A. , Riethmüller R.
Published: May 2018

The transport of suspended particulate matter and of heavy metals in tidal rivers is of both ecological and economic relevance. But temporal variabilities and spatial heterogeneities considerably complicate its quantitative treatment by numerical simulation and the acquisition of representative field data for systematic investigations. As a contribution to the potential solution of this problem, a methodology has been developed at the GKSS Research Centre which combines theoretical and experimental techniques in an effective way. A novel measuring system on board a ship allows the fast determination of hydrographie parameters, and water samples are taken in parallel from different depths. Various analytical techniques are applied for quantitative trace-element detection. The experimental data are used as boundary conditions in hydrodynamic and transport model calculations. In the paper, the experimental equipment, techniques, and numerical models are described. Some results of first promising investigations are presented: Lateral distribution of water transport, tidal variation of vertical turbidity profiles, settling velocities, cumulative transp.ort of suspended matter and heavy metals, dissolved and particulate heavy-metal contents and, in part, their tidal variations.
Biological Effects and Pollution Assessment
Authors: McIntyre A. D.
Published: May 2018

Techniques for studying biological effects of pollution in the sea are briefly reviewed and the circumstances under which they are most useful in coastal waters considered. Some approaches are particularly suitable for studying pollution hot spots, others for detecting low levels of contamination. The role of the scientist in pollution assessment is discussed and the problems caused by lack of ecological understanding highlighted.
Mersey Estuary (U.K.) Bird Mortalities – Causes, Consequences and Correctives
Authors: Wilson K. W. , Head P. C. , Jones P. D.
Published: May 2018

In late 1979 there was an extensive mortality amongst the newly arrived over-wintering populations of waders, wildfowl and gulls in the Mersey Estuary. Mortalities on this scale were unprecedented in the area and there was no obvious cause although circumstantial evidence collected during the months following the incident indicated the probability of acute poisoning by trialkyl lead compounds.

The principal source of trialkyl lead compounds was the discharge to the Manchester Ship Canal from a factory producing tetraalkyl lead petroleum additives. Under certain conditions of freshwater flow and tidal movements appreciable concentrations of trialkyl lead could occur in the adjacent waters of the Mersey Estuary. The persistence of trialkyl lead in the estuarine waters provided a suitable source for its up-take by benthic fauna and subsequently birds in amounts similar to those shown to be acutely toxic in laboratory experiments.

Simple empirical models were used to calculate an appropriate effluent quality standard to protect waders and wildfowl. Full co-operation was received from the factory concerned and the levels of trialkyl lead discharged have been reduced to the standard. Levels of alkyl lead in the water and in estuarine fauna have fallen in line with the reduced discharge. No bird mortalities attributable to alkyl lead have been observed since the lower discharge levels have been consistently achieved.
Transport and Water Quality Modelling in the Southern North Sea in Relation to Coastal Pollution Research and Control
Authors: van Pagee J. A. , Gerritsen H. , de Ruijter W P. M.
Published: May 2018

Mathematical modelling techniques are used to quantify the transport in the southern part of the North Sea of pollutants originating from various inputs. Special attention was given to the anthropogenic increase in local concentrations of nutrients (N, P) and heavy metals (Cd, Hg, Cu, Pb, Zn, Cr) and their potential impact on marine organisms.

A depth-averaged hydrodynamic model is used to calculate tidal and wind driven velocities and water levels. By averaging, residual flows are calculated, forming the basis for advective transports in a water quality model. Dispersive transports are derived from a comparison of simulated and observed salinity distributions. Water mass distributions and age functions for various inflowing water types are determined with the model. Transports of nutrients and heavy metals in the southern part of the North Sea are calculated using annual pollution inputs for 1980. Although interactions with bottom sediments are not considered, the calculated and measured concentrations show good similarities.

The water quality in the Dutch coastal zone and German Bight area is shown to be highly determined by local pollution loads from the rivers Rhine, Weser and Elbe respectively. Comparison of simulated concentrations for 1980 with those resulting from simulations with estimated natural river inputs, shows that more than 50% of nutrients and heavy metal concentrations originate from human activities in large coastal zone areas. From toxicological information and standards, it is concluded that Cd, Hg and Cu are substances that need special attention in pollution research and control for the Dutch coastal waters.
The Performance of the Rotating Disc System under the Tropical Conditions in Taiwan
Authors: Cheung Pak-Shing
Published: May 2018

In this investigation, the discharge from a septic tank and community wastewater were treated in a pilot scale rotating disc system (RDS) to evaluate the performance of this system under the tropical conditions in Taiwan, with the intention of developing design criteria useful for this region. It was found that by varying the organic loading to the system, different degrees of treatment could be obtained. Results of this study indicated that with an organic loading of 8-10 g B0D/(m2, d), 90% removal of BOD as well as NH4-N removal could be achieved. Ambient temperature was found to have no significant effect on the treatment efficiency, and the optimum hydraulic detention time was within 3 hours. Biological sludge production amounted to 0.6-0.8 kg/kg BOD removed.
Studies on the Contact Biofilter as a Compact Process in Domestic Sewage Treatment
Authors: Somiya I. , Tsuno H. , Ono Y.
Published: May 2018

This paper describes the treatment performance of a newly developed compact treatment process, named the “contact biofilter”. It is composed of a submerged biofilter and a granular medium filter. The research experiments on the process were conducted using domestic sewage. It was clearly shown that this process could reduce SS and total BOD in effluent to below 10 and 20 mg/l, respectively, in a short retention time, and it can be used as a secondary treatment process. The organic substances in sewage are effectively recovered as sludge without extensive mineralization.
Oxygen Depletion Modelling, Port Shelter, Hong Kong
Authors: Krogsgaard Jensen J. , Malmgren-Hansen A. , Mortensen P.
Published: May 2018

In order to describe and evaluate the effect on the oxygen concentrations of a planned sewage outlet in the Port Shelter Bay in Hong Kong, a relatively simple BOD-DO-box model has been established. The model describes the oxygen concentration in 6 horizontal boxes in the central part of Port Shelter. Each box is vertically divided into 4 layers (sub-boxes). The oxygen concentration in each layer is described as a function of the vertical and the horizontal mixing, the oxygen demand of the sediment and the concentration of organic matter in the water. A finite difference transport dispersion model provided input data for the BOD-DO model.

Two main calculations have been made: one simulating the cold season (15°C) and one simulating the warm season (30°C). Furthermore sensitivity analyses have been carried out.

The calculations show an oxygen depletion of approximately 1 and 2 mg O2/l at 15° and 30°C respectively in the bottom layer over an area of approximately two sq. km. The highest oxygen depletion is calculated in the bottom layer. From the calculation it can further be concluded that the decay rate of organic matter in the water and the vertical mixing will influence the oxygen depletion considerably. In periods where either the decay rate is higher than 3 d−1, or the vertical mixing is considerably low an oxygen depletion higher than the calculated can be expected. The lowest measured oxygen concentration in Port Shelter during the period July-August 1982 was 1.7 mg O2/l. Therefore it can be expected that the planned outlet will cause oxygen-free or nearly oxygen-free conditions in the bottom layer in warm periods with low vertical mixing.
Simultaneous Nitrogen and Phosphate Removal by the Intermittent Cyclic Process
Authors: Hayakawa N. , Tsuji J. , Hamamoto Y.
Published: May 2018

By using the Intermittent Cyclic (IC) process which repeats aerobic and anaerobic conditions in an 18-m3 pilot plant reactor, domestic sewage was treated at a rate of 18 m3 per day. Operating condition was 4 cycles per day, intermittent aeration--4 hours, settling--1 hour, drawing--1 hour.

Seven months of operation recorded high nitrogen removal rates: mean 86% and maximum 96%, phosphate removal rates: mean 83% and maximum 93%. Compared with conventional aerobic/anaerobic processes, the IC process, one of batch-type treatment processes, can advantageously and stably remove nitrogen and phosphate with repeated aeration and nonaeration under optimal control.
Performance of Sequencing Batch Reactor Activated Sludge Processes for Simultaneous Removal of Nitrogen, Phosphorus and Bod as Applied to Small Community Sewage Treatment
Authors: Okada M. , Sudo R.
Published: May 2018

Laboratory-scale sequencing batch reactor (SBR) activated sludge process was fed with synthetic wastewater to clarify the possibility of simultaneous removal of nitrogen, phosphorus, and organic substances by modifying operational schedule. Anoxic and/or anaerobic reactions in addition to aerobic reactions were introduced into a cycle of batch operation. Simultaneous removal of nitrogen, phosphorus and organic carbon was shown to be possible by the modified operation of SBR into which reactions without aeration (anoxic/anaerobic) were introduced during the fill period. Oxidized nitrogen remaining in the reactor at the end of the former cycle was removed by denitrification during the fill. Anaerobic conditions after the denitrification was completed enhanced phosphorus release from the sludge and the following luxury uptake during aeration removed phosphorus from water. Both extension and reduction of anoxic/anaerobic period in the beginning of a cycle damaged phosphorus removal and sludge settlability. Thus, an optimum length of period for these reactions must be chosen for successful operations. The best length of this period coincided with that of the fill within the range of this study.
The Possible Utilization of Waste Sludge as an Adsorbent for Removal of Organic Vapor
Authors: Chiang P. C. , You J. H.
Published: May 2018

In this investigation it was found that the waste sludge obtained from a municipal sewage treatment plant could be reclaimed as an adsorbent for removal of organic vapours, i.e. toluene, methyl-ethyl-ketone and 1-1-2-trichloroethylene, through use of a pyrolysis technique. In order to find the optimum manufacturing process, several tests were performed under various conditions in which the addition of a catalyst, temperature control, and residence time in the furnace, were considered as the three major factors. Both the reclaimed adsorbent and commercially available activated carbon were evaluated to determine their adsorption capacity at various influent concentrations of organic vapours.
Heavy Metals in Drinking Waters from the Paraiba Do Sul – Guandu River System, Rio De Janeiro State, Brazil
Authors: Azcue J. M. , Pfeiffer W. C. , Fiszman M. , Malm O.
Published: May 2018

The main goals of the present work are the determination of the critical metals in the Paraiba do Sul - Guandu River System (PSR-GR), and the analysis of tap waters supplied to local cities as well as the city of Rio de Janeiro, to evaluate the metal pollution. Results show that four metals (Pb, Cu, Cr and Zn) out of eight released by the local industrial area are the critical metals in the PSR-GR system. Suspended particles are the main compartment in transporting these metals downstream. Analysis of the performance of tap water treatment plants pointed out the main parameter for these treatment plants is the retention of suspended particles. Iron and manganese had the highest concentrations.
Survival and Adhesion of some Pathogenic and Facultative Pathogenic Micro-Organisms in Groundwater
Authors: Filip Z. , Kaddu-Mulindwa D. , Milde G.
Published: May 2018

Land application of sewage and sewage sludge, incorrect draining off of wastewater, and also accidents, can lead to contamination of groundwater with pathogenic and facultative pathogenic micro-organisms. If no inactivation or elimination of such contaminants takes place, the hygienic quality of groundwater can be negatively affected. In model experiments carried out in the laboratory, the survival of Escherichiacoli, Salmonellatyphimurium, Yersiniaenterocolitica, Pseudomonasaeruginosa, Staphylococcusaureus, StreptococcusfaecalisBacilluscereus, Bacillusmegaterium, Clostridiumperfringens, Aspergillusniger, Nocardiaalba and Streptomycesgriseus in groundwater kept at 10°C was tested. Although no apparent proliferation of the micro-organisms was observed during the experiments, most of them survived for an extended period up to 300 days. Only B.megaterium and S.aureus were not detectable after 12 and 30 days, respectively. Sand originating from a groundwater aquifer, and also the enrichment of the groundwater with humic acid and potassium nitrate as sources of carbon and nitrogen did not affect microbial survival substantially. Adhesion of micro-organisms to sand was observed, which may influence both the persistence and transportation of micro-organisms in the aquifer. The results of these experiments can be of importance for determining groundwater protection zones.
Activated Sludge Process Control by Behaviour of Secondary Settling Tanks
Authors: d'Antonio G. , Carbone P.
Published: May 2018

The mathematical models of activated sludge kinetics and solids flux have been investigated; the constants have been derived experimentally. By developing the equations of the two models, an operational chart for activated sludge process control has been plotted.
Legal Aspects of the Disposal of Industrial Wastes on Soil
Authors: Mendes J M. O.
Published: May 2018

It is, clearly, a Government responsibility to enact laws and promulgate regulations for control of industrial pollution.

The main techniques for soil industrial wastes disposal, namely, landfarming and landfilling, profit from the extensive knowledge acquired, in past decades, in the field of water and air pollution control and must be analysed within a comprehensive system for hazardous waste management, with its legal and administrative aspects.

This paper presents some general principles of a Hazardous Waste Management System, which are broadly applicable, regardless differences between States or Countries. Finally, it discusses the specific case of Hazardous Wastes Management in the State of Bahia, Brazil and makes some suggestions for its improvement.