bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long‐Term Benthic Monitoring of a Dense Effluent Discharge to Sea
Authors: D. CRAIG N. C. , SHILLABEER N. , PARR J. C. W. 
Published: July 2007

AbstractThe paper describes and discusses the effect on the local benthic community of the discharge of a dense, saline, effluent into a nearshore area of the North Sea. The monitoring programme continued through the twenty‐year period from 1970 until 1989 and includes effectively five years pre‐discharge data. Samples were taken from fixed stations with a grab sampler and the invertebrate fauna were identified, wherever possible, to species. In addition, the particle size distribution of the sediment in each sample was determined. The discharge has had a clear effect on the benthic community.This extensive dataset, with its clear gradient of effect, also offers the opportunity of comparing the effectiveness of species and family level identification when studying the effect of disturbance. In this case the impacted area was as readily identifiable from the family as the species level data.
The Development of a Sludge Disposal Strategy for the Hong Kong Territories
Authors: LOWE P. 
Published: July 2007

AbstractSludge arisings in the Hong Kong Territories are predicted to increase from the current level of 44 300 tDS/annum to 314000 tDS/annum. This has led to a need to examine the treatment and disposal facilities required for the future. Disposal facilities were found to be restricted, with virtually no suitable land for a liquid disposal route and a sea route limited to the present quantities. Only landfill remained as the major disposal outlet, but this is also limited by the moisture absorbence capacity of the emplaced material and limiting metal concentrations.In order to match the sludge production to the disposal outlet capacity, a series of process options was considered. Transportation studies using pumping, road and sea networks were undertaken and the environmental impact assessment of introducing thermal technologies was reviewed. Finally the various options were evaluated using a modified version of the Water Research Centre's WISDOM model.
Groundwater Nitrate Concentrations from the Old Chalford Nitrate‐Sensitive Area, West Oxfordshire
Authors: EVANS D. , MOXON I. R. , C. THOMAS J. H. 
Published: July 2007

AbstractThis paper, describes nitrate concentrations in a groundwater catchment currently designated as a nitrate‐sensitive area. Although the scheme has been operational for two years, groundwater nitrate concentrations have regularly exceeded the EC maximum admissible concentration of 11.3 mg/1 NO3‐N (50 mg/1 NO3) from sources draining both arable and grassland management regimes. Nitrate levels from arable areas tend to produce a seasonal pattern of winter leaching and summer uptake, whilst no such pattern or fluctuation is observed from grassland areas. Four processes are defined which regulate nitrate inputs to the saturated zone of the Great Oolite aquifer: (i) availability of ‘free’nitrogen, (ii) variations in nitrogen uptake, (iii) leaching of nitrates from the soil environment, and (iv) limited atttenuation within the unsaturated zone.
Diffuse Sources of Pollution by Heavy Metals
Authors: ZABEL T. F. 
Published: July 2007

AbstractSignificant reductions in the amount of heavy metals released to the aquatic environment have been achieved by applying strict controls on point source industrial discharges. Because of these tight controls, diffuse pollution sources have increased in importance as a contribution to the total load. Diffuse inputs originate mainly from the use of chemical products. Thus control of these inputs can be achieved by refraining from or limiting the use of these products or by restricting the amount of heavy metals permitted in such products. Control of diffuse sources of heavy metals could be based on a ‘positive approval’system, permitting only those uses which do not lead to environmental harm and which could not be replaced by less harmful alternatives. Assessing the environmental impact of the alternatives will require the introduction of a ‘cradle to grave’approach.
The Occurrence and Viability of Giardia Cysts in Scottish Raw and Final Waters
Authors: SMITH H. V. , ROBERTSON LUCY J. , GILMOUR R. A. , MORRIS G. P. , GIRDWOOD R. W. A. , SMITH P. G. 
Published: July 2007

AbstractThe occurrence of Giardia cysts in Scottish raw and potable waters was investigated. Giardia cysts were detected in 49% of raw waters, with concentrations of up to 1.05 cysts per litre, and in 19% of final waters, with concentrations of up to 1.67 cysts per litre. In some of the positive water samples the viability of the cysts was assessed by viewing the cyst morphology and inclusion/exclusion of propidium iodide. Viable cysts were detected in a proportion of both raw waters and positive final waters studied. Further investigations at 21 water‐treatment plants revealed cysts in 9 (43%) of the raw waters, and in 4 (19%) of the final waters. Cysts were only detected in the final waters of plants in which cysts were also detected in the raw water. These data indicate that viable Giardia cysts may be ingested with potable water in Scotland.
The Influence of Unlined Boreholes on Groundwater Chemistry: A Comparative Study Using Pore‐Water Extraction and Packer Sampling
Authors: PRICE M. , WILLIAMS ANN 
Published: July 2007

AbstractIn the consolidated formations which form most of the major aquifers in the UK, many monitoring boreholes are left unlined (open) for their effective length. They therefore provide pathways for groundwater to flow from one part of the aquifer to another.A borehole was core‐drilled through Triassic sandstones into Permian mudstones at a site in North Yorkshire. Pore water was extracted from the core and compared with conventional depth samples and with samples taken from intervals isolated using packer systems: (a) during drilling, (b) about one month after drilling, and (c) two years after drilling.The study revealed that natural flow down the borehole led to rapid changes in the quality of water in some parts of the formation.The implication is that open boreholes can act as conduits to allow flow to take place from one part of the aquifer to another. They are therefore not reliable as sampling points, and may actually accelerate the vertical spread of pollutants. However, this last effect should not be over‐stated; in this study, the flow down the borehole was equivalent to the natural flow through only a relatively small area of land.
Monitoring the Effect of Sewage Effluent on the Oxford Canal Using Chironomid Pupal Exuviae
Authors: WILSON R. S. 
Published: July 2007

ABSTRACTCollections of chironomid pupal exuviae from the Oxford Canal were taken monthly from May to October 1991 at stations above and below the sewage effluent discharge at Kidlington, near Oxford.The chironomid exuvial assemblages showed clear changes reflecting the effects of the sewage, notably in the increased dominance of Parachironomus arcuatus and Chironomus riparius and other pollution‐tolerant species downstream from the effluent inflow. A return to the pattern of taxa seen in the upstream stations was noted below the next canal lock, 2.8 km downstream from the effluent discharge.Environmental quality indices, calculated according to the Chironomid Pupal Exuvial Technique, also reflected the effects of the sewage inflow.The results show that chironomid populations, as sampled by collecting pupal exuviae, are potentially valuable for monitoring organic pollution in canals.
Mapping Turbidity, Surface Temperature and Water Circulation Patterns with the Aid of Satellite Imagery
Authors: BABAN S. M. J. 
Published: July 2007

ABSTRACTWater turbidity, surface temperature and circulation of Barton and Wroxham Broads, two of the Norfolk Broads, were studied using one reflective (TM1) and the thermal (TM6) TM band. The results indicated that the through‐flowing path of the River Ant in Barton Broad is the major influence on the distribution of these parameters. In Wroxham Broad, both turbidity and surface temperature displayed a uniform distribution. This could be explained by the absence of a predominant direction of flow.
A Standardized Low‐Cost Low‐Flow Gauging Station
Authors: BARTON B. M. J. 
Published: July 2007

ABSTRACTThis paper describes the origins and development of a simple, low‐cost, low‐flow stream gauging station to meet the operational requirements of a major water resource management system. The utilitarian design uses standardized, prefabricated components in order to achieve maximum economy and ease of construction without sacrificing durability or hydrometric accuracy.
Experiences of Digested Sludge Thickening by Aercon
Authors: LYNCH M. , STEPHENSON T. 
Published: July 2007

ABSTRACTIncreasing restrictions on sewage sludge disposal routes and the tightening of treatment requirements have led to an escalation of sludge‐disposal costs which are out of proportion to other sewage‐treatment costs: consequently reducing sludge volume is becoming increasingly cost‐effective. Consolidation of anaerobically digested sludge has traditionally been difficult and takes many weeks in secondary digesters or deep storage tanks. Pre‐aeration of the sludge using the Aercon process can enable consolidation to take place in days instead of weeks.This paper reports the results of a pilot‐scale plant designed to investigate further the mechanism by which aeration speeds up consolidation. It was concluded that the rate of consolidation depended on aeration intensity and cooling of the sludge. Inhibition of anaerobiosis was more important than gas stripping in enhancing consolidation.
Examples of Groundwater Modelling in Environmental Assessment Studies
Authors: ASHLEY R. P. 
Published: July 2007

ABSTRACTThe development of groundwater modelling techniques is reviewed, from analogue and early digital models to current commercial software packages. The parallel development of the application of groundwater modelling as a tool for evaluating the impact of developments and structures on hydrogeological systems is also examined. Formerly, new model programs were written for each application, requiring that the user had programming skills as well as hydrogeological expertise, and model development periods were measured in months or years. Now, a knowledge of the program details is not necessarily a prerequisite for a satisfactory model, which may be designed, constructed, calibrated and used in days or weeks. However, a thorough understanding of the conceptual model underlying a software package, and of the numerical methods used to generate the output, is as important as ever. Examples are given in the paper of the exploitation of commercial packages to produce rapid assessments of the impact on groundwater of proposed mineral workings and similar developments.
Impact of the River Maine Drainage Scheme on Hydro‐Power Generation
Authors: COCHRANE S. R. , HIGGINSON N. N. J. 
Published: July 2007

ABSTRACTA comparison is made between pre‐ and post‐drainage scheme river flows recorded on the River Maine, Co. Antrim. A method of using five‐year reference periods has been applied to the mean daily flows to smooth and eliminate, as far as possible, variations due to climatic changes.Any loss of energy production which might have been due to changes in river flow was examined for turbine installations at a factory at Cullybackey. The quantities of usable water, and hence potential energy production, were calculated for each of the post‐scheme five‐year periods and compared with a pre‐scheme five‐year reference period. Any potential loss was then represented by a depreciation factor. It was found that no measurable loss of potential energy production has occurred on the River Maine in the post‐scheme period.
Trials Using a Mobile Ultraviolet Disinfection System in South West Water
Authors: JOB G. D , TRENGOVE R. , REALEY G. J 
Published: July 2007

ABSTRACTUltraviolet radiation has been shown to be effective for disinfecting secondary effluents, and the National Rivers Authority has given conditional approval for its use at sites where disinfection can be justified.This paper describes the findings of disinfection trials on five different sewage works' effluents using low‐pressure ultraviolet systems. The study examines and compares the disinfection performance of clean units and their deterioration in performance due to fouling effects. Conclusions are drawn on the effectiveness of ultraviolet disinfection in the removal of pathogens and pathogen surrogates.
The Life‐Cycle Analysis of Small‐Scale Sewage‐Treatment Processes
Authors: EMMERSON R. H. C. , MORSE G. K , LESTER J. N , EDGE D. R. 
Published: July 2007

ABSTRACTThe environmental impact of small‐scale sewage‐treatment works has been evaluated using the technique of ‘life‐cycle analysis’. Three sewage‐treatment works with different process options were analysed to identify and quantify material use, energy use and environmental releases during construction, operation and demolition. This enabled (i) a comparison to be made between process options, and (ii) the identification of opportunities for the improvement of environmental performance. Subject to satisfactory sewage treatment and sludge disposal, the technique identified additional impacts of importance, which have implications for energy management, works design, supplier management and general environmental policy. Life‐cycle analysis provides a useful insight into environmental impact and has potential for wider application within the water industry.
The Pre‐design of Berenplaat Water‐Treatment Works, Rotterdam: Additional Processes to Achieve Biologically Stable Water
Authors: RODMAN D. J , VAN DE VEER A. J. , HOLMES J. F 
Published: July 2007

ABSTRACTBiological regrowth in a water distribution system can be avoided by either maintaining a free chlorine residual to suppress growth or controlling conditions which may support growth, or by a combination of both. Micro‐organisms will grow in water only if nutrients are present in sufficient amounts; conversely the reduction of biodegradable nutrients in water is vitally important in controlling the regrowth of microorganisms and zooplankton in the distribution system. The measurement of assimilable organic carbon has been developed as a way of evaluating the concentration of biodegradable material which is available to support such biological growth.This paper describes the pilot‐plant and full‐scale studies carried out at the Berenplaat water‐treatment works, Rotterdam to (a) improve disinfection, (b) eliminate the formation of trihalomethanes and other halogenated compounds formed by chlorination, and (c) reduce the final water assimilable organic carbon concentrations to very low levels, so that a high degree of biological stability can be maintained in the distribution system.
Mechanisms of Leakage through Synthetic Landfill Liner Materials
Authors: BUSS S. E. , BUTLER A. P , SOLLARS C. J , PERRY R. , JOHNSTON P. M 
Published: July 2007

ABSTRACTThe introduction of synthetic lining materials for leachate containment and the prevention of groundwater contamination was an important development in landfill technology. These materials have a low hydraulic conductivity which results in minimal leachate release by bulk fluid flow (advection) provided that the barrier (and its construction) is free from defects. However, the effectiveness of these materials as barriers cannot be confirmed unless contaminant release by diffusion is also taken into consideration.This paper reviews the mechanisms by which transport through barriers occur. It highlights the role of diffusion as a pathway for organic compounds to migrate through synthetic liners and indicates its importance in terms of environmental impact and landfill design.
The Degradation of Atrazine and Other Pesticides by Photolysis
Authors: BOURGINE F. P , CHAPMAN J. I , KERAI H. , DUVAL J. L , GREEN J. G , HAMILTON D. 
Published: July 2007

ABSTRACTGroundwaters from chalk aquifers which are used as a supply for drinking water are often contaminated with pesticides ‐ in particular, atrazine. This paper discusses the use of an industrial‐scale ultraviolet chamber to reduce the concentration of atrazine in a chalk‐derived water which is used for drinking water supply. The concentration of atrazine varied between 0.1 μg/l and 0.5 μg/l, and the raw water was spiked when necessary. Results for other pesticides contaminants are also presented.The efficiency of atrazine removal is dependent only on the energy input and is constant, regardless of the initial concentration. Hydrogen peroxide improves the efficiency of ultraviolet irradiation but requires high doses.
Reed‐Bed Treatment for Municipal and Industrial Wastewater in Beijing, China
Authors: LI S. R , DING T. , WANG S. 
Published: July 2007

ABSTRACTThe reed‐bed system is a cost‐effective and environmentally friendly method of treating sewage from small treatment works. A pilot‐scale plant, which treated 500 m3/d of municipal and industrial waste‐water, was studied in Beijing, China. The aim of the project was (i) to test the ability of the reed beds to remove pollutants for long‐term operation in cold weather conditions, and (ii) to evaluate its environmental, ecological and financial values. The results of operation demonstrated that this system has the ability to remove the pollutants. One of the attractive features is that the reed beds can partly convert the pollutants into plant biomass with the natural energy from sunlight. The reeds can (a) be harvested each year, (b) provide a wildlife habitat, and (c) improve the quality of the ecosystem. Capital and operating costs of the system are comparatively low.
The Incidence of Cryptosporidiosis in Comparison with other Gastro‐Intestinal Illnesses in Blackpool, Wyre and Fylde
Authors: FEWTRELL L. , DELAHUNTY A. 
Published: July 2007

ABSTRACTThe paper describes a study which was carried out to examine the incidence of cryptosporidiosis and other gastro‐intestinal illnesses in Blackpool, Wyre and Fylde. Information on the incidence of cryptosporidiosis, between 1987 and 1992, was collected retrospectively. Between July 1992 and June 1993, prospective information on a range of gastro‐intestinal illnesses was obtained from individual cases using a specially designed questionnaire.In the six‐year period of the retrospective study, 497 cases of cryptosporidiosis were reported. When spatial patterns of cryptosporidiosis reporting were examined, no relationship could be found with either the water supply zone or census ward. The prospective study produced similar results to the retrospective investigation. Recreational water use and farm animal contact were identified as ‘risk factors’ for cryptosporidiosis when compared with other gastrointestinal illness aetiological agents.
Reservoir Outlet Works in the Mid‐1990s
Authors: EARP D. N. W. 
Published: July 2007

AbstractThe paper reviews developments which have been carried out during the last hundred years in the design and construction of outlet works for water supply and river regulating reservoirs in the UK. The review covers diversion tunnels, culverts, valve towers, upstream control equipment, in‐line valves, pipeline materials and flow control valves. It concludes with a brief description on the rehabilitation of the outlet works at a number of nineteenth‐century reservoirs.
Cost‐Effective Water‐Quality Modelling of Potable Water Distribution Systems
Authors: LINDLEY E. , DAVIES S. E. 
Published: July 2007

AbstractBefore privatization of the water authorities in England and Wales in 1989, future water companies were instructed to provide auditable proof of their investment requirements by the production of asset management plans.With respect to distribution systems for potable water, asset management plan studies have established that unlined ferrous mains are often the main cause of complaints about discoloured water. It has also been found that the investment in water mains rehabilitation, which is driven by water quality problems, overshadows similar investment requirements driven by high burst rates and poor hydraulic performance.This paper describes how certain techniques of water quality modelling have been developed and refined to provide a rapid, cost‐effective method for identifying requirements for water‐main rehabilitation.
Uprating Water‐Treatment Works Supplying the Thames Water Ring Main
Authors: Glendinning D. J , Mitchell J. 
Published: July 2007

ABSTRACTThis paper outlines the measures which were taken at Thames Water's major water‐treatment works to uprate their hydraulic capacity in meeting the projected demands of the Thames Water ring main. In addition, the integration of advanced water‐treatment processes, in the form of ozonation and granular activated‐carbon filtration, is also highlighted.
Environmental Influences on Company Valuations
Authors: Young P. J 
Published: July 2007

ABSTRACTThe benefits accruing from good environmental management of companies are most often linked to economic benefit and the concept of moving towards sustainable development. However, the link between environmental liabilities, assets, or performance, and the financial valuation of a company remains obscure at best. Operational improvements, for example from implementing a waste minimization programme, can give a clear short‐term reduction in costs, and impact immediately on profits. Many environmental risk management programmes also need to deal with long‐term issues such as historical land contamination and changes in manufacturing technology. These have a much more protracted and ultimately fundamental impact on the perceived capital value and future prospects of a company. This paper seeks to describe how the relationship between environmental and financial risk management is becoming clearer, and uses examples to show how this is brought into focus during merger and acquisition activities.
Refurbishment of Control Structures on the River Avon at Strensham Lock
Authors: Lewis R. I. 
Published: July 2007

AbstractThree control structures at Strensham lock maintain the water level in the upstream pound of the River Avon for navigation, ecology and angling purposes. The National Rivers Authority †, which currently owns the structures, is responsible for their maintenance and for the operation of the vertical‐lift sluice gates which are opened to control flooding. Construction work has recently been completed to secure the structures, which were in a poor state of repair and in danger of collapsing. The two sluice structures were completely rebuilt and the weir was modified.The paper describes the planning, design and construction of the works, which are located within a ‘site of special scientific interest’.
Effluent Control: The Hong Kong Approach
Authors: Holmes P. R. 
Published: July 2007

AbstractWater pollution has existed for many years in Hong Kong, but the Government's strategy for pollution control is now beginning to take effect. The strategy includes planning, legislation, and the provision of sewage‐disposal systems. In the past, the main thrust has been against traditional pollutants measured by BOD, suspended solids and various nutrients, but as these are brought under control, attention will be given to the need to control toxic pollutants. The existing policy and legislation does not deal with toxic pollutants well, and past work on toxic substances in Hong Kong has concentrated on individual chemicals. The Environmental Protection Department is now seeking to (a) develop ecotoxicological expertise to identify toxicant pathways in the environment, (b) introduce water‐quality objectives for toxic substances which it can monitor effectively, and (c) improve standards for effluent control.