bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects on the Ecosystem of Sewage Sludge Disposal from a Pipeline
Authors: Bascom W
Published: May 2018

About 57,000 m tons (dry wt) of sewage sludge has been discharged each year for the last 22 years at the brink of a steep-sided submarine canyon in Santa Monica Bay, California. The discharge point is 100 meters deep and 10 km offshore. An area of about 3 sq km of the upper canyon has been substantially changed by the high concentration of sewage solids but the ecosystem is stable. There are fewer species of invertebrates but more species of fish in the canyon; the biomass of both fish and invertebrates is larger than controls. In the region near the canyon rim there are extraordinary populations of clams and molluscs; fishing is far above average for the bay. This solution to sludge disposal causes both negative and positive effects which seem to be about balanced.
Sludge Disposal to Sea in the Federal Republic of Germany†
Authors: Fuchs D
Published: May 2018

Sludge disposal to sea in Germany is on the one hand dependent on the quantities requiring disposal, the handling methods and treatment processes used. On the other hand the regulations for waste disposal to sea in Germany must be observed and the priority given to landbased methods. In addition the national authorities in issuing a permit have to take into account existing scientific knowledge and exercise judgement. It is firmly intended to terminate sludge disposal to sea completely and sewage sludge has to meet the requirements for its use in agriculture.

†This paper should be included in Theme 3 - Case Histories.
Education and Training of Operators in the Federal Republic of Germany
Authors: Pluemer C H
Published: May 2018

Treatment works are becoming high grade installations requiring sophisticated operation and maintenance. Production of well educated and trained operators is required if one is to avoid economic losses and damage.

In the Fed.Rep. of Germany three grades of operators are trained:

Klärwärter

Klärfacharbeiter

Klärmeister

The training includes experience in the field, lectures and examinations. Each grade needs a certain time of experience at a treatment plant. In neighbourhoods further training is offered. Highly trained staff have their own workships, seminars and congresses to exchange knowledge.
Surface Dilution of Round Negative Buoyant Jets–A Comparison with Other Jets
Authors: Noutsopoulos G , Demetriou J
Published: May 2018

Experimental results, concerning surface dilutions of round turbulent jets with negative buoyancy, are presented and discussed. Fresh water jets, of density ρo, discharging from a vertical pipe, of internal diameter do, placed in the middle of the experimental tank, at a depth H from the free surface of a quiescent ambient liquid, consisting of common salt water solution, of density ρs, slightly larger than ρo, have been studied.

Dilution measurements, made with a conductivity probe, have been performed, along radial traverses, at a small depth of 5do, below the free surface. The experimental results were analyzed and presented in terms of dimensionless dilution scale gl versus the dimensionless length scale zl. In this form they are directly compared to axial dilution results of the positive buoyant jet. With the proper definition of length scale, they are expressed satisfactorily by the well established semiem-pirical expressions, concerning the axial dilution of positive buoyant jets. Semiem-pirical relationships, concerning the axial dilution distribution of the horizontal buoyant jet, are also presented. Thus, a direct comparison is made possible for surface dilutions in the three round buoyant jet cases, namely the positive, the negative and the horizontal jet, which will be very useful in engineering design.
An Appraisal of the Performance of a Continuous Automatic Fish Biomonitoring System at an Industrial Site
Authors: Morgan W S G , Kühn P C , Allais B , Wallis G
Published: May 2018

A fully automated biological monitoring system, employing sensor fish locomotory behaviour pattern response to intoxication, has been installed at a pulp and paper mill (SAPPI KRAFT LTD.) at Mandini, Natal, South Africa. This system detects insidious toxic conditions in the effluent discharge. The installation and operation of the system are discussed, and the environmental and industrial benefits to be gained from the use of such systems assessed. Installation and operation costs are presented and the necessity for future research examined.
Quality and Quantity of Stormwater Runoff from a Commercial Land - Use Catchment in Natal, South Africa
Authors: Simpson D E , Kemp P H
Published: May 2018

The methodology used to estimate annual imports of nitrogen, phosphorus and some heavy metals by atmospheric fallout, and the export by stormwater runoff from a 12 ha commercial land-use catchment is described. An automatic flow and rainfall monitoring system was used. Import and export rates of pollutants for successive years are compared and the contribution of atmospheric fallout to runoff loads is assessed. The relationships found by regression analysis between certain water quality parameters are presented, together with confidence levels. The Stormwater Management Model (SWMM) was tested using measured catchment parameters and simulated and observed hydrographs are compared. Predicted loadings for some pollutants are compared with measured values.
Organic Micropollution of Potable Water Supplies: Indirect versus Direct Reuse
Authors: van Rensburg J F J , Theron S J , Hassett A J , van Rossum P G
Published: May 2018

The quality of the drinking-water produced by an indirect reuse system and a direct reuse system was evaluated with respect to organic micropollutants. The quality of the water produced by the direct system was superior to that produced by the indirect system. No adequate multiple barriers against organic and bacteriological contaminants were found in the indirect reuse system, as opposed to the direct reuse system where these barriers are provided. Coprostanol, a faecal sterol, was found to be a useful qualitative indicator of faecal pollution in water. Several indicators for organic macropollution, as well as organic pollution indices as indicators for organic micropollutants, were evaluated.
Limnological Effects of the Elimination of Phosphorus from the Wahnbach Reservoir
Authors: Bernhardt H , Clasen J
Published: May 2018

The elimination of the phosphorus compounds from the River Wahnbach (100 - 150 µg/l Ptot) at the point where it flows into the Wahnbach Reservoir down to a figure of 5 µg/l Ptot has decreased the total phosphorus concentration in the Wahnbach Reservoir to 8 - 10 µg/l Ptot. As a result of this, the impoundment which had been in an eutrophic state became oligotrophic to mesotrophic within 3 years. The blue-green algae which had been predominant disappeared and diatoms grow again every spring. Algal growth has been reduced to such an extent that the transparency has gone up to a Secchi-depth of 10 m and was 6 m on an annual average. This was solely produced by eliminating phosphorus and without eliminating nitrogen at the same time (the annual average N-concentration of all tributaries was 5 mg/l).
The Effect of Aeration Basin Configuration on Activated Sludge Bulking at Low Organic Loading
Authors: Lee S-E , Koopman B L , Jenkins D , Lewis R F
Published: May 2018

Continuous-flow laboratory-scale activated sludge units were operated on domestic sewage at low F/M. In CSTR units at the F/M range of 0.05–0.25 g COD removed/g TMLVSS, day bulking did not occur with a weak (BOD5 = 139 mg/L) sewage feed and TMLSS = 1.5 g/L. Supplementation of sewage by blending with raw sludge produced a stronger sewage (BOD5 = 315 mg/L) which caused TMLSS to increase to 3.5 g/L. Bulking occurred in CSTR, 2, 4, 8, and 16 compartment units. An aeration basin with initial compartment l/32nd of aeration basin volume prevented but did not cure bulking. An aeration basin with initial compartments 1/74th of aeration basin volume, prevented and cured bulking. Anoxia in an aeration basin with two initial compartments each 1/64th of the total aeration basin volume did not aid in curing bulking. The SVI of sludges at low F/M (0.3–0.35 g COD removed/g TMLVSS, day) and high TMLSS (3.5 g/L) is related to conditions in the initial compartment rather than those in the remainder of the aeration basin. Initial compartment soluble COD, first-compartment F/M, and initial compartment size are important; floc loading, dispersion number and total number of aeration basin compartments are not important.
Obtaining Secondary Treatment with RBC/Underflow Clarifiers
Authors: Bogert I L
Published: May 2018

A one-year experimental program conducted at Edgewater, New Jersey, U.S.A. evaluated the concept of providing secondary treatment by the installation of rotating biological contactors (RBC's) in modified primary sedimentation tanks.

A primary tank was divided horizontally into two zones separated by an intermediate floor. Four RBC's were placed in the upper zone. The lower zone provided secondary sedimentation. High rate primary sedimentation was provided to remove grit and trash without removing substantial portions of BOD and SS.

The experimental program funded by the U.S. EPA and the Borough of Edgewater was conducted over a full year at different loads. The system proved to be an effective secondary treatment process with little difference in treatment efficiency between summer and winter conditions.
The Scale-Up and Limitation of Physical Oxygen Transfer in Rotating Biological Contractors
Authors: Kim B-J , Molof A H
Published: May 2018

Three different sized laboratory scale Rotating Biological Contactor (RBC) units were constructed to study the controlling factors of physical oxygen transfer. Physical parameters were identified and evaluated by the volumetric oxygen transfer coefficient (KLa) from non-steady state clean water tests. The controlling factor was found to be the liquid film flow rate per unit volume and the function could be practically expressed as w1.5 D0.5 S−1. The turbulene effect on the free water surface and subsurface volume becomes comparatively less significant as the disk size increases. The data indicated that the physical oxygen transfer contribution to the biological treatment oxygen requirement became less significant than oxygen transfer through other mechanisms as the disk size increases.
The Performance of an Ultrafiltration Pilot-Plant for the Closed Loop Recycling of Textile Desizing Effluents
Authors: Buckley C A , Townsend R B , Groves G R
Published: May 2018

The results of sixteen months operation of an Ultrafiltration pilot-plant for the closed loop treatment and recycle of textile desizing effluent containing polyvinyl alcohol are described. The operation in the batch concentration and continuous modes are compared. Data on the effects of feed temperature, reject flowrate, size concentration and membrane cleaning on the permeate production rate are presented. The environmental impact and economics of a full-scale plant are discussed.
Leaching Characteristics of Industrial Metal Finishing Wastewater Treatment Plant Solids
Authors: Goodgame T H , Barnett P W
Published: May 2018

The safe disposal of industrial wastes is an international problem of increasing magnitude. There are very limited disposal sites for wastes which are hazardous in nature. The purpose of this study was to determine the leaching characteristics of solids resulting from the treatment for discharge of wastewaters produced by typical large metal finishing facilities.

Samples were chosen so that the full range of both manufacturing processes and products produced were covered. The primary processes which contributed to the wastewater for treatment were “phosphating” in preparation for organic coating and “pickling” in preparation for application of porcelain enamel.

These samples, along with a sandy loam soil as a control, were placed in lysi-meters. Distilled water was used as the leaching liquid, as being most representative of landfill conditions. Liquid was passed through the samples at the rate of one liter per week. Based upon the area of the lysimeter this rate was equivalent to a percolation rate of 510 cm per year. Leachate samples were analyzed for twenty-two different parameters: pH, TSS, COD, alkalinity, chloride, nitrate, phosphate, sulfate. Al, B, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Na, Ni, Pb, Ti and Zn.

The results of these tests indicate that the WWTP solids act very similarly to the soil used as a control. The leachate concentrations of heavy metals and the depletion of the heavy metals were such that this material would create no problems if disposed in an ordinary landfill – indicating that it is neither toxic nor hazardous. The time frame of this experiment was equivalent to ten years exposure in an ordinary landfill, and to a much longer period if deposited in a sanitary landfill.
Funding Water Pollution Control in South Africa
Authors: Lusher J A
Published: May 2018

Water pollution control in South Africa is discussed from the point of view of cost and available sources of revenue. It is shown how state interests in water are generated and how the present system of water pollution control is derived from this. An example concerning the mineralisation of the water resources of the central Transvaal industrial area is used to illustrate social cost. The position of local authorities with regard to income and expenditure on water-based services is examined in detail. The role of the State in these matters is determined. The conclusions drawn from the survey and a discussion of the elementary theory of water price are used to construct a motivation for a tax system, designed to curb pollution and to reimburse major water purchasers.
Suppression of Density Waves in Clarifiers
Authors: Murphy Michael C , Hudgins R R , Silveston P L
Published: May 2018

Experiments on a 4-ft (1.2-m) diameter model circular clarifier operating at overflow rates and suspension concentrations corresponding to municipal treatment practice show that baffles designed to function as wave traps suppress low-frequency, large-amplitude density waves observed in these units. Simultaneous measurements of solids removal show substantial improvement. This work establishes the relationship between density waves and the deviation from ideal clarifier performance that earlier papers on internal waves by our research group suggested. The power spectrum of the internal waves and the effect of operating variables such as overflow rate, scraper speed, and suspended solid on the spectrum and solids removal are discussed.
Hygienic Quality of Sewage Sludge Compost
Authors: Nell J H , Steer A G , van Rensburg P A J
Published: May 2018

The numerous bacterial, viral, protozoal, helminthic and fungal pathogens in sewage are concentrated in raw sewage sludge during primary sedimentation. Anaerobic digestion, air-drying and activated sludge treatment may reduce the levels of these organisms, but a risk to human health still remains. Although the magnitude of this risk cannot be quantified or even predicted at this stage, the probability of infection must be minimised to protect the community. Composting reduces the health hazard by decreasing the virulence (numbers and viability) of pathogenic organisms. Results of experiments conducted by the NIWR showed that total coliforms, E. coli, coliphage, Salmonella and Ascaris ova can be eliminated in less than a week in a pilot-scale composter utilising dewatered raw and air-dried digested sludges with wood chips and refuse as filler material. In full-scale plants elimination of indicator organisms took much longer, depending on the degree of control exercised.
The Use of Sewage Sludge in Agriculture
Authors: Coker E G
Published: May 2018

The whole field of utilisation of sewage sludge for the production of agricultural crops is surveyed. Special attention is given to the development of a long-term strategy for utilisation of sewage sludges as fertilisers for agricultural crops, to the benefits arising from the organic matter, nitrogen, and phosphorus which they contain, to the limiting factors to the use of sewage sludges for this purpose, and to those crops which are most appropriate to use. Consideration is given to the use of sewage sludge in land reclamation.
Metals in Sewage Sludge and their Potential Effects in Agriculture
Authors: Coker E G , Matthews P J
Published: May 2018

Metals accumulate in sewage sludges from domestic and industrial sources. Where such sludges are used in agriculture, the metals may contaminate land to such an extent that the quality and yield of crops is affected. Control of the industrial sources of sludge applications will avoid these problems. The paper reviews available information in the chemistry of the most significant potentially toxic metals in soils and their effects on crops including contamination of the food chain ending with man. The paper emphasises the large body of information available but underlines the need for more data if greater certainty is to evolve in the guidelines produced for the agricultural use of sludge and trade effluent control.
Review of Water Pollution Problems and Control Strategies in the South African Mining Industry
Authors: Kempe J O
Published: May 2018

Water resources in South Africa are limited. It is inevitable that in a climate of expanding industry and economy, total salt loads discharged both from point and non-point sources will increase. The effect of this on these resources will soon assume crisis proportions unless effective treatment for the removal of salt loads from effluents is exercised and rigid constraints imposed on effluents not conforming to prescribed quality standards.

The mining industry is a large user of water and a major contributor to salt load entering streams, rivers and encatchments. Special attention is given to the use of water and discharge of effluents by this large and important industry.
The Handling and Disposal of Coal Ash in the Cegb in Relation to the Aqueous Environment
Authors: Brown J , Ray N J
Published: May 2018

Pulverised fuel ash (pfa) and furnace bottom ash (fba) are the principal solid wastes from modern coal fired plant. These residues are often handled and disposed of as slurries and pfa is frequently used for the reclamation of derelict land.

The disposal of excess water from the handling operation after the ash has been allowed to settle in a pond or lagoon is the first interaction with the aqueous environment that needs to be considered. In CEGB, the discharge of such effluents to rivers is governed by consents laid down by Water Authorities. The state of the art is such that the required conditions can be met in once-through handling systems without undue difficulty but one factor which requires careful management is the level of suspended solids in the outfall when a lagoon is nearly full.

Whether ash is disposed of wet, or merely conditioned with water to facilitate handling. there may be a further need to consider the percolation of water through the ash and its possible interaction with groundwater. This calls for knowledge or study of the ash itself, the size of the area to be reclaimed, the rainfall pattern and the local hydrogeology, including the size and rate of recharge of the aquifer. Each case needs to be considered on its merits. The basic CEGB approach to this aspect of ash disposal is discussed; it requires the combination of laboratory studies of percolate quality with hydrogeological assessment to evaluate the potential risk, if any. The actual consent to dispose of ash, taking such factors into account, is made by the Local Authority in consultation with the Water Authority.

The present view of ash disposal relative to the aqueous environment could be disturbed if legislation and the associated Codes of Practice were to become more stringent. Recent control measures which are pertinent to these activities are, therefore, considered and comment made on their content and application.
Comparison of Different Methods for Estimating the Leaching of Heavy Metals from Coal Combustion Waste
Authors: Reuss Merete
Published: May 2018

Literature on the different leaching methods for estimating the heavy metal content in coal fly ash was studied and is herein summarized. Attention is given to some of the practical problems which must be addressed in planning a leaching test.

Strong acid digestion and several methods for the determination of total metal concentration are discussed. Results of leaching experiments with 6 different fly ashes are reported. Ag, As, Cd, Cr, Cu, Hg, Mo, Ni, Pb, Se, V, Zn, Na, K, Ca, and Mg were determined. These same metals were determined by atomic absorption spectrophotometry after both nitric acid and hydrofluoric acid digestion. The two digestion methods are compared.
Use of “The Capillary Barrier” as a Shield against Groundwater Pollution from Fly-Ash Deposits
Authors: Andersen L J , Madsen B
Published: May 2018

The enormous amounts of fly-ash produced by the burning of coal in power plants have resulted in a number of environmental problems, not least of which is the increased risk of groundwater pollution from its deposition in gravel pits. In order to prevent this pollution, fly-ash deposits have often been established with an underlying membrane. Such membrane-systems are quite expensive to build and necessitate besides a continous pumping and removal of percolate. The alternative of covering the fly-ash with a low-permeable membrane, which removes the infiltrated water laterally, prevents not only groundwater pollution but also the formation of percolate. By using the principle of “The Capillary Barrier”, the lowpermeable membrane can be constructed of natural and resistant porous materials.
The Role of Soil in Determining Surface Water Composition
Authors: Bache Bryon W
Published: May 2018

Incoming precipitation in rural areas passes through soil and weathering rock during passage to surface waters. The composition of the effluent is determined by its hydrologic pathway and by the material through which it flows. Reactions between water and soils or weathering rocks are normally rapid compared with typical residence times, so that the composition of water is derived from the material through which it has passed. Composition data for groundwater, drainage and surface waters illustrate these principles. Apparent deviations are explained by low residence times or unusual catchment properties, and show that detailed mineralogical and physiographic information is important for catchments in sensitive areas, if the factors controlling water composition in these areas are to be understood.
Potential Off-Flavour Compounds from Chloro-Bleaching of Pulp and Chlorodisinfection of Water
Authors: Paasivirta J , Knuutinen J , Tarhanen J , Kuokkanen T , Surma-Aho K , Paukku R , Kääriäinen H , Lahtiperä M , Veijanen A
Published: May 2018

Chlorobleaching of pulp is the most important source of organochlorine pollutants in the Finnish aquatic ecosystems. Similar types of pollutants are formed during chlorodisinfection of water. The model compound approach employed in our laboratory has revealed the structures and amounts of pollutants formed and has made the interpretation and assay of individual organochlorine compounds in the environment possible. Tainting of fish near chlorination plants is frequently observed. Especially chlorinated phenols and anisoles (microbial metabolites of the former) are chlorination products which are known to have a strong odour and taste at very low concentrations. Other chlorinated products, which are potential tainting substances, e.g. halogenated hydrocarbons, acids, aldehydes and ketones were also studied. Contents of some organochlorine pollutants in pikes of Middle Finland were compared with the taste panel evaluation of the same fish samples.
Volatile Compounds of the Cyanophyceae – A Review
Authors: Slater George P , Blok Vivian C
Published: May 2018

A relationship between blue-green algae and off-flavours in water was reported as early as 1883. Continuing research has shown that two metabolites, geosmin and methylisoborneol are major contributors to unpalatable flavours in water and aquatic organisms. Many instances of the co-occurrence of these two compounds and dense blooms of blue-green algae have been recorded. Cultures of Anabaena, Lyngbya, Osciiiatoria, and Sympioca species have been shown to produce geosmin or methylisoborneol while blooms of Aphanizomenon, Anabaena, Microcystis, Oscillatoria, and Gomphosphaeria have been found in water containing geosmin or the odour of this compound. Actinomycetes have also been shown to produce these two compounds.

In addition to geosmin and methylisoborneol, there is evidence that several other blue-green algal metabolites contribute to aquatic taste and odour problems. Among them is β-cyclocitral which has a distinctive tobacco flavour. Blue-green algae produce a variety of organic compounds including hydrocarbons, fatty acids, aromatics, ketones, terpenoids, amines and Sulfides which could contribute to the over-all flavour of water and aquatic organisms.
Factors Influencing Geosmin Production by a Streptomycete and their Relevance to the Occurrence of Earthy Taints in Reservoirs
Authors: Wood S , Williams S T , White W R , Jones F
Published: May 2018

Water Authorities in the U.K. receive complaints about taste and odours of chemical and biological origin in water supplies. Earthy flavours associated with actinomycetes, cyanobacteria and/or combinations of these are most prevalent. The study area consisted of five large open reservoirs, four of which have sporadic flavour problems. The possible sources of odourous metabolites were studied (water mass, sediment, plant debris, soil run-off). The water mass required high concentrations of nutrients before actinomycetes produced geosmin; such were not reached in the reservoirs. Sediment yielded geosmin after exposure to air for four weeks and plant debris was found to support geosmin production. The soil surrounding the reservoir supports geosmin production and may contaminate the water by run-off or seepage through the reservoir walls.
Odor Problems in Lake Biwa
Authors: Yagi M , Kajino M , Matsuo U , Ashitani K , Kita T , Nakamura T
Published: May 2018

In 1969 a musty odor was first found in the southern basin of Lake Biwa. Since then we have been investigating the causes of the problem. In the 1970's musty odor problems commonly occurred from May to early June due to the metabolites produced by Phormidiumtenue. However, the problem which took place in the summer of 1981 was found to be caused by an algal bloom of Anabaenamacrospora.

The analyses of the water taken in the lake as well as of the laboratory cultures of the blue-green algae led to the conclusion that 2-methylisoborneol is produced by Phormidiumtenue, whereas geosmin by Anabaenamacrospora.

Purge and trap concentration followed by mass fragmentography was developed and applied as a measurement method for these two odorous compounds. The method was found to be rapid, reproducible and sensitive enough to detect them at a nanogram per liter concentration level or beneath their threshold odors, requiring only a small sample (100 ml).

Slow sand filtration was found to be effective in removing odor, where the odorous compounds were reduced to less than 10 ng/l in the effluents.
Use of Microcosms for Evaluation of Toxic Substances
Authors: Huckabee J W , Brocksen R W
Published: May 2018

Microcosms are designed to help understand certain ecosystem processes, rather than to replicate functional ecosystems. The rationale for their use is that they provide information (e.g. on the behaviour of toxic substances) at the process level. The microcosm is not an undisturbed natural system, but retention of critical subsystems enables it to be used as a simulation of nature. The major problems which have been encountered in the use of microcosms concern replicability (precision); in general, the larger or more complex the system, the greater its value for the maintenance of reality, but the poorer its reproducibility. Several points should be considered when applying the microcosm as a tool in toxicology: (1) a hypothesis should be tested; (2) the experiment must be realistic; although (3) pragmatically the design is a simulation,not a reproduction of an ecosystem; (4) testing should be at the process level; and (5) reproducibility should be demonstrated. Examples are presented of complex microcosms which have given reproducible results. It is recommended that microcosms are useful research tools when used in conjunction with other approaches (bench top experiments and field observations).
Water Treatment Considerations–Aquatic Humus
Authors: Gjessing E T
Published: May 2018

For several reasons the surface waters in cold climate areas are coloured due to humic substances. There are two major objections against humus in drinking water, the first is concerned with aesthetical and practical problems and the second is due to indirect negative health effects. There are essentially three different methods in use today for the removal or reduction of humus colour in water: (1) Addition of chemicals with the intention of reducing the “solubility”, (2) Addition of chemicals in order to bleach or mineralize the humus, and (3) Filtration with the intention of removal of coloured particles and some of the “soluble” colour. The treatment processes are discussed.
Disposal and Treatment of Concentrated Human Wastes
Authors: Prasad D , Heinke G W
Published: May 2018

Many communities in Canada's northern areas rely on trucked supply of water and pickup of human waste from bucket toilets or holding tanks. The high capital cost of conventional piped water and gravity sewer systems and the lack of funds necessitate the continued used of trucked systems for many years, particularly in the smaller settlements in permafrost regions. Promising methods of cheaper piped collection of wastes,such as vacuum and pressure sewers may be used in the near future. Both require only small quantities of water for transport of solids. Human wastes in plastic bags (“honey-bags”) are now disposed of at a dump, in waste pits or lagoons. Satisfactory treatment methods for these strong wastes and for wastes from holding tanks, vacuum and pressure sewers are needed.

Results of a five year study simulating a waste pit in permafrost show that it merely serves as a holding tank and does not provide satisfactory treatment. Pathogens are likely to remain viable in such a pit for many years. Anaerobic digestion of undiluted human waste has been found feasible at 20° C, but is not likely to be a practical and economical solution for communities using trucked systems. Properly located, constructed and operated waste pits are recommended for these situations.

Conventional anaerobic digestion of vacuum sewer wastes or holding tanks wastes which are much less dilute than sewage, is feasible at a temperature of 20° C and with a minimum detention time of 30 days. The process may be applicable at lower temperatures, provided a high proportion of methane bacteria is maintained in the reactor. This may be accomplished either by longer detention time or through the anaerobic contact process. However, anaerobic filter treatment of these wastes appears to be most practical, economical and effective, providing about 85% and 80% COD reduction for detention times of 3 and 8 days at 25° C and 10° C respectively. It is recommended that a pilot installation can be constructed in a northern community using anaerobic filter as the method of treatment of vacuum or pressure sewer wastes or holding tank wastes.
Beneficial Use of Sewage Sludge in the Gothenburg Region, Sweden
Authors: Hallquist Sören
Published: May 2018

It has proved to be hard to find an adequate and sufficiently large site for final disposal of wastes in the urbanized Gothenburg Region. The reasons are both the actual situation and the public opinion. So efforts have been made and money spent in order to convert the undigested sewage sludge into products which are appropriate for beneficial purposes. After unsuccessful attempts with thermal treatment the Gothenburg Regional Sewerage Company - GRYAAB - has chosen to produce two different sludge products, compost and lime treated sludge. In order to demonstrate that the products are useful several tests have been carried out. The studies should, however, not be regarded as scientific agricultural and horticultural work, but as one part of the marketing procedure of the products.
Sewage Treatment in Abu Dhabi
Authors: Paul P N , Smith L J
Published: May 2018

The history of sewage treatment in Abu Dhabi since 1973 is briefly reviewed. The commissioning of the new treatment works in 1982 is described with particular reference to aspects of process chemistry under Middle East conditions. Points concerning extreme septicity occasioned by long retention in the pumping mains are emphasised.
Nakdong Estuary Barrage and Land Reclamation – Morphological Aspects
Authors: Eysink W D
Published: May 2018

The construction of the barrage will change the flow conditions in the entire estuary which will interfere in the present equilibrium between channel dimensions and flow conditions. Consequently, morphological changes in the estuary have to be taken into account.

Generally, the cross sectional area of a tidal channel shows a distinct relationship with a characteristic tidal prism passing that section. Also here such a relation could be found and was applied to predict the new equilibrium state of the estuary. Estimates of the time required for adaptation have been based on the total sediment volumes required for this and the future sediment transport pattern which must supply those volumes.

The morphological study provided a basis for proper decisions on matters such as: selection of the barrage location, maintenance dredging and levee heights. It also gave the effects of the barrage on the tidal-flat area which, as an important bird habitat, has the official status of a national monument. In particular these effects and the aspects of maintenance dredging seaward of the barrage are discussed as they are major phenomena for the ecological impact of the barrage.
Maximization of Cost-Effectiveness in Environmental Analyses for Coastal Engineering Projects
Authors: Brown S , Wardle T M
Published: May 2018

Environmental studies for coastal projects are often constrained by budgets and schedules. Consultants must use cost and schedule effective methodologies for data collection and impact evaluation, and for designing adequate mitigation and compensation measures. The complex jurisdictional relationships frequently inherent in environmental legislation, necessitates careful coordination with various government agencies in order to ensure adequate study design. An empirical study strategy has been developed by Acres Consulting Services Ltd. based on a multidisciplinary task structure that is oriented to the specific permit requirements of approving agencies.

Satellite imagery interpretation is a key feature of the strategy which assists in minimizing costly field programs. The design of protection, mitigation and compensation measures based on an assessment of species vulnerability is also included. Examples are given of studies in the fiords, and estuaries of coastal British Columbia for port, industrial and mining developments.

The results suggest that the adoption of an integrated strategy encompassing multidisciplinary studies, can facilitate greater cost-effectiveness in environmental investigations for coastal zone management.
River Outfalls, Estuaries and the Marine Environment
Authors: Lester W F
Published: May 2018

Theme 2 deals with the quality aspects of discharges from rivers to estuaries, direct discharges to estuaries, the twice daily influx of sea water mixing with the water remaining in the estuary and the effect of the estuary discharge on the adjacent marine environment.

The paper compares the flow characteristics and qualities of the Rivers Medway, Trent and Severn at the tidal limits at different periods and indicates the effect of these discharges on the quality of the upper reaches of the estuary. The extent and distribution in place and time of the oxygen sag in the Trent estuary is recorded as also is the concentration of cadmium and ammonia in the Severn estuary.

The physical characteristics of the estuaries are described and reference is made to the statute law relating to control of estuarial pollution.
Water Quality Management in Sakarya River Basin: I. Planning Phase
Authors: Ethem Gönenç I , Orhon Derin , Artan Reha
Published: May 2018

This article deals with the planning of water quality management studies of the “Sakarya River Basin Management Project” which was submitted to NATO Science Committee for support through the Science for Stability Program. The background and justification of the project are described and then the objectives are presented by phases. The activities that have already been carried out in the planning and the feasibility phases are discussed. A detailed account is given of the procedure for mathematical model development and application, and the methodology for monitoring system design.
The Gulf Coast Waste Disposal Authority: A Regional Approach to Water Quality Management
Authors: Jack Davis L
Published: May 2018

The Gulf Coast Waste Disposal Authority is a regional public agency created by the State of Texas to design and implement water quality management systems in three counties surrounding Galveston Bay. This article will outline the water quality management strategy employed by the Authority for a highly industrialized and populated region. Regional treatment and public and private sector cooperation will be presented as a management objective for muncipal and industrial waste disposal. A description of the background and operations of the Authority will be included along with examples of joint or combined wastewater treatment.

The pressing problem of hazardous waste management in Texas will be discussed. The Authority's experiences with facility siting and public reaction will be summarized and a new approach to help resolve these issues will be presented. The article will conclude with some thoughts on strategic planning for public managers.
Review of Rainfall Data Application for Design and Analysis
Authors: Arnell V , Harremoës P , Jensen M , Johansen N B , Niemczynowicz J
Published: May 2018

This review has been prepared for the international seminar: Rain fall as the basis for urban runoff design and analysis, held in Copenhagen, 24'26 Aug. 1983. The purpose of the review is to bring a state of the art within, 1) the statistical characterization of rain fall in time and space, 2) the development of synthetic design storms and, 3) the application of both synthetic design storms and historical storms to pipe design, flooding prediction, design of detention basins and calculation of the yearly or extreme pollutiona1 load on receiving waters from combined sewer overflows. The main conclusion, primarily related to item 3), is that more attention in this context should be put on statistical analysis of the detrimental effects: flooding and pollution. This analysis is best performed by applying historical rain records. Realistic flooding prediction is believed only to be possible with a fully dynamic flow model, whereas pollution may be studied by means of simpler models like the time area approach. The outstanding problem in the statistical prediction is the distribution in space of the historical rains.
Suppression of Actinomycete Scum Production – A Case Study at Senboku Wastewater Treatment Plant, Japan
Authors: Hiraoka M , Tsumura K
Published: May 2018

The Senboku wastewater treatment plant had suffered from bulking caused by the Actinomycete, Nocardia amarae. The purpose of this paper is to report the causes of the actinomycete scum production in this treatment plant and the methods of suppressing the scum production which resulted in success.
Control of Simultaneous Denitrification by a Nitrate Controller
Authors: Kayser R , Ermel G
Published: May 2018

In completely mixed aeration tanks simultaneous nitrification-denitrification is achieved by a proper control of aeration. A NOx-controller was developed and successfully tested for aeration control. Considerable power savings were obtained.
Nitrification and Phosphorus Removal from Trickling Filter Effluents
Authors: Bundgaard Erik , Kristensen Gert Holm
Published: May 2018

Nitrification and simultaneous phosphorus precipitation in a separate activated sludge plant is considered the cheapest alternative for upgrading conventional trickling filter plants.

Before upgrading the Herning treatment plant (200,000 PE) a 12 month pilot plant experiment was performed. During operation of the pilot plant, important parameters were investigated, such as excess sludge production, sludge properties, and influence of the large part of chemical sludge when combining separate nitrification and simultaneous precipitation.

It was found that a stable process could be operated with a bypass of 20-25% settled raw wastewater. Due to improvements in the sludge characteristics simultaneous precipitation with ferrous sulphate improved the effluent quality with respect to both phosphorus, BOD and suspended solids.
Operating Experience with Plastic Media Tertiary Trickling Filters for Nitrification
Authors: Gujer W , Boller M
Published: May 2018

Based on 20 months of pilot experience the following aspects of operation of a nitrifying tertiary trickling filter are discussed: Biomass production, biomass predation, approach to steady state, load variation, alkalinity, stability of performance, nitrite, temperature and nitrification in multi media filtration. Nitrification in tertiary trickling filters proved to be easy to operate, stable in performance and cost efficient in comparison with activated sludge processes.
Experiences with Polishing Lagoons
Authors: Imhoff KR
Published: May 2018

For upgrading of overloaded biological plants the addition of polishing lagoons is feasible. Operational results of eleven polishing lagoons are reported. In addition, one plant has been intensively studied in respect to the cumulative distribution of BOD5, COD, and phosphorus. Design recommendations are given.
Modelling of the Transport of Chlorinated Hydrocarbon Solvents in Groundwater: A Case Study
Authors: Kinzelbach W K. H.
Published: May 2018

At present chlorinated hydrocarbon solvents rank among the major pollutants found in groundwater. In the interpretation of field data and the planning of decontamination measures numerical transport models may be a valuable tool of the environmental engineer. The applicability of one such model is tested on a case of groundwater pollution by 1,1,1,-trichloroethane. The model is composed of a horizontally 2-D flow model and a 3-D ‘random-walk' transport model. It takes into account convective and dispersive transport as well as linear adsorption and a first order decay reaction. Under certain simplifying assumptions the model allows an adequate reproduction of observed concentrations. Due to uncertainty in data and limited comparabili ty of simulated and measured concentrations the model parameters can only be estimated within bounds. The decay rate of 1,1,1-trichloroethane is estimated to lie between 0 and 0.0005 l/d.
Detection of Rotavirus in Treated Drinking Water
Authors: Keswick B. H. , Gerba C. P. , Rose J. B. , Toranzos G. A.
Published: May 2018

The removal of naturally occurring viruses was studied at a full scale 9m3/sec (205 mgd) water treatment plant. Rotavirus was detected in 41 of 113 large volume samples collected after successive stages of the water treatment process. Virus recovery was highest during the summer rainy season when water quality declined. Rotavirus was recovered from 3 of 26 finished water samples which met acceptable limits for turbidity, total coliform bacteria and residual chlorine. Water from heavily polluted sources which meets water quality guidelines cannot be assumed to be virus free.
Inactivation of Hepatitis a Virus by Heat and Formaldehyde
Authors: Flehmig B. , Billing A. , Vallbracht A. , Botzenhart K.
Published: May 2018

The GBM strain of hepatitis A virus adapted to a fetal rhesus monkey kidney cell line (Frhk-4/R) was treated and inactivated at several different temperatures and with several different formaldehyde concentrations. Heat inactivation showed that no inactivation occurred after treatment for 60 minutes at 37°C. Treatment for 60 minutes at 50°C reduced infectivity by 1 log 10 step ; treatment for 60 minutes at 60°C, by 4 log 10 steps. Treatment for 30 minutes at 70°C resulted in complete inactivation of HAV. Complete inactivation by formaldehyde treatment was achieved only with a 0.35% concentration. Treatment with lower concentrations resulted in incomplete HAV inactivation.
Detection and Stability of Enteric Viruses in Sludge, Soil and Ground Water
Authors: Jørgensen P. H. , Lund E.
Published: May 2018

Digested sludge from a municipal sewage treatment plant was systematically placed on the surface of pure diluvial sand in a forest plantation. In the area examined, sludge application started in September. Viruses could be demonstrated in the sludge deposits up to 21 weeks but not 22 weeks after the application. Polio-, coxsackie- and adenovirus types were detected. The method employed was elution with beef extract at pH 8 followed by hydroextraction. No virus was demonstrated in soil samples 5 weeks after sludge application. Ground water samples from bores established before sludge application were examined employing 5 litre samples, but these were all negative. Four larger samples (30 to 100 1) were examined. One 30 litre sample contained poliovirus type 2 and coxsackievirus type B3. It was collected in the 11th week after sludge application at a depth of 3 m under the surface. The 3 other samples were negative.

A soil sample of 30 kg collected at a depth of 35 to 100 cm was brought to the laboratory. Aliquots of 300 g were suspended in ground water from the area in flasks of 500 ml. Antibiotics were added. The pH was 4.5. In the same way a system employing a sandy loam soil was set up. Here the pH was 7.2. In each series 3 flasks were seeded with coxsackievirus B3, adenovirus 1 and echovirus 7 respectively. The flasks were completely filled with water, stoppered airtight and kept dark at 4° to 7°C. During an 8 month period 20 ml samples were taken 7 times after mixing. The samples were centrifuged. The supernatant and eluates of the sediments were examined for virus. Adenovirus was not demonstrated in the supernatants, echovirus only in the one from the sandy soil, while coxsackievirus was demonstrated in both supernatants. Except for adenovirus in the sandy loam soil the viruses were quite stable in the sediments. Ground water samples seeded with the same 3 viruses were set up in parallel but without added soil. The results obtained from these water samples were quite similar to the sediment samples except for echovirus which could not be demonstrated in the ground water from the sandy soil area after 2 months.