Integrated Coastal Management and River Basin Management

There are important functional relationships between river basins and coastal areas and one may influence the other. The two systems are linked through natural processes (water flow, sediment transport, energy) and human activities (urban development, rural activities, technical infrastructures, waste and pollution). Coastal areas are extremely valuable as they concentrate a rich diversity of natural habitat areas and a large variety of natural resources. River basins are also important areas from the point of view of natural ecosystems particularly on the basis of the presence of water and its support for the flora and fauna in the area. Coastal areas and river basin, at the same time provide opportunities for development of a wide range of human activities. The coastal zone is an essential part of a river basin. Both, river basin and coastal problems require a multi-sectoral approach. In some cases the two systems require a common framework of management. The goals, general objectives and principles of integrated river basin and coastal zone management are discussed.     

Evaluating Demand Management Aspects of Urban Water Policy. The City of Volos Case,Greece

This paper examines the perspectives of the implementation of a demand-oriented policy concerning residential water use, which covers almost 70% of urban water. Water demand, water pricing policy, as well as building capacity are examined and evaluated in order to investigate the current situation in urban water management in the city of Volos with reference to residential water use. The application of IWR-MAIN model in order to estimate future water needs and form different scenarios for sustainable water resources management together with a field survey in various water issues conducted in 966 citizens of the city of Volos justify the urgent need for the adoption of a demand driven policy.     

Climate-influenced hydrobiogeochemistry and groundwater remedy design: A review

The process of designing a remedy for contaminated groundwater historically has not commonly included climate-future, hydrologic, and biogeochemical aquifer characteristics. From experience, the remedy design process also has not consistently nor directly integrated or projected future hydrologic and biogeochemical effects of the human-induced or developed environment—aka the anthropogenic influence—on potential remedy performance. The apparent practice of (1) not regularly assessing anthro-influenced hydrological (termed here as anthrohydrology) or biogeochemical characteristics (collectively hydrobiogeochemistry) of a site and (2) rarely accounting for future climatic shifts as design factors in remedy design may be due, in part, to the general practice-level view that groundwater remediation systems (whether in situ or ex situ) have seldom been anticipated to last more than a few years (or one or two decades at the most). Second, methods to reliably and quantitatively estimate site-specific, climate-future shifts in groundwater conditions using global and/or regional climate models and the resultant impacts on contaminant plume characteristics have not been readily available. The authors here suggest that while the concept of remedy design resilience and durability, within an envelope of climate change and anthropogenic influence, has been discussed in some technical circles as a component of “sustainable remediation,” we have found that direct application of these technical concepts in quantifiable terms remains rare. By incorporating the potential influence of future hydrobiogeochemical scenarios into remedy design, however, the design process could account for reasonable climate-induced influence on the groundwater system for a given site. These scenarios could then be applied within the remedy selection process to assess performance durability under potentially changing hydrologic, biological, and chemical conditions.     

Bench‐ and pilot‐scale applications of electrochemical peroxidation: A new remedial concept

Electrochemical peroxidation (ECP) is a proprietary process that utilizes sacrificial iron electrodes and stochiometrically balanced applications of hydrogen peroxide to efficiently destroy aqueous phase contaminants. In laboratory trials it has been successful in reducing, often to non‐detectable levels, BTEX, fuel additives, chlorinated solvents, and polychlorinated biphenyls in ground waters. The process has also been found effective in reducing the chemical and biological oxygen demand of industrial waste water. Agency‐approved pilot tests will be conducted at two gasoline spill sites during 2000 where traditional pump and treat methods have proven ineffectual because of ground water chemistry or subsurface hydrologic conditions. The ECP process utilizes a tripartite treatment strategy consisting of 1) ex situ chemical oxidation; 2) in situ oxidation by reinjection of treated water with residual oxidants at the head of the plume; and 3) reestablishment of aerobic biodegradation by alteration of subsurface redox conditions. In contrast to other in situ oxidation treatment methods, dissolved iron is derived electrochemically, negating the need for ferrous salt addition. Dilute hydrogen peroxide (3 percent) is incrementally added to maximize oxidation efficiency and eliminate safety and environmental concerns accompanying the use of highly concentrated solutions. Results of laboratory trials and the geological and geochemical considerations of upcoming pilot‐scale applications are presented. Other potential applications currently under investigation include combination with other remedial processes (e.g. permeable barriers and hydrogen release compounds) to insure complete and rapid contaminant mineralization.     

运用灰色GM（1,1）系统模型预测北京市污水排放量

北京市水资源开发利用已经超过了水资源承载能力范围,由此引发的水资源短缺问题日益严重.对污水的综合利用进行研究可以达到持续利用水资源的目的,解决水资源短缺问题.以北京市2005-2012年污水排放量资料为基础,运用灰色系统模型,对工业、生活污水排放量及总污水排放量进行了预测,分析北京市污水排放量走势及存在的问题,提出未来北京市污水综合利用的对策措施.     

Groundwater and Nutrient Discharge into Jiaozhou Bay,North China

The health of near shore marine ecosystems has long been a concern because of its importance to coastal areas. Jiaozhou Bay (JZB) is one such marine ecosystem experiencing rapid water quality degradation in the last several decades. From the area surrounding the bay, the nutrients discharged into the bay through surface water and groundwater has been greatly changed. The thickness of the aquifers and the permeability is relatively high, the concentrations of nutrients in the groundwater are generally high, and so the groundwater discharged into JZB is very significant. However, no attempt has ever been made to evaluate the amount of nutrients discharged into the bay area via groundwater. In this study, the cross-section method and water balance method were used to estimate the amount of groundwater and nutrients discharged into JZB via the subsurface. Groundwater was monitored and sampled at aquifers surrounding the bay area, and some previously available data was also analyzed. The results indicated that groundwater from the Baisha Aquifer east of JZB now is the major source of nutrients (nitrate, dissolved SiO₂) being discharged into the bay. The concentrations of nutrients in the groundwater have been increasing with intensive agricultural land use. However, Dagu Aquifer, the largest aquifer north of JZB, only provides limited nutrients to the bay area because of the construction of a low permeability subsurface dam. Historically, during the 1970s to the 1990s, the Baisha Aquifer experienced seawater intrusion due to excessive groundwater withdrawal. The same was true for the Dagu Aquifer from the 1980s to the 1990s. Because of this, no significant nutrients were discharged into the bay.     

Thermal decomposition of guaiacol in sub- and supercritical water and its kinetic analysis

The conversion of biomass waste into resources as a recycling process is receiving increased interest due to the perceived need for a sustainable global carbon cycle and environmental considerations. Several treatment processes are being developed. Hydrothermal treatment is one of the most effective approaches, because water at high temperatures and high pressures behaves as a reaction medium with remarkable properties. In this work, the reaction behavior of guaiacol as a biomass model compound was studied in subcritical water at 483–563 K and in supercritical water at 653–673 K using a batch reactor. Guaiacol can be considered representative of the aromatic ring structures present in lignin, a major component of woody biomass. The chemical species formed in aqueous products were identified by gas chromatography/mass spectrometry and quantified using high-performance liquid chromatography. The effect of pressure and reaction time on the conversion process of guaiacol is discussed. The results obtained indicate that this method has potential for efficient organic waste conversion.     

Recent trends and current practices for secondary processing of zinc and lead. Part I: lead recovery from secondary sources.

Implementation of stricter environmental laws and economic reasons has forced all the metallurgical industries to go for eco-friendly technologies to produce metal and other related products. However, generation of wastes is an integral part of metallurgical industries. If the wastes/residues are hazardous in nature, they generally have to be treated or/and disposed of in safe and designated dumping sites. If these wastes/residues are non-hazardous in nature, then they may be suitable for use as secondary raw material to recover metals such as lead, copper etc., which are in growing demand all over the world. The processing of lead secondaries is important because of their relative high metal content, as well as the low energy and cost involved in recovering the metal. This paper mainly focuses on the current practices and recent trends in the secondary processing of lead. Various processes, particularly hydrometallurgical ones, already developed or in the development stages, are discussed. Attempts made by various Council of Scientific and Industrial Research (CSIR) Laboratories including the National Metallurgical Laboratory (NML) and industries such as Binani Zinc to develop eco-friendly processes for the recovery of lead from secondary raw materials are also described.     

A Simplified Model for Predicting the Pollution Exchange Coefficient of Small Tidal Embayments

In recent years there has been a significant increase in the development and application of ever more sophisticated multi-dimensional models for solving the hydrodynamic and constituent transport equations which govern the flushing of pollution. However, advanced numerical modelling techniques can sometimes be augmented by alternative mathematical approaches which use simplified analytical solutions to predict the dispersion of contaminants. In the present article, a novel analytical tidal prism model is described for predicting the pollution flushing characteristics of small tidal embayments. The model relates the water quality response of the basin to the external forcing effects of the tide, the initial pollutant loading and the freshwater inflow rate. In general, the pollution flushing not only depends upon the geometry of the embayment and the tidal range but also on the proportion of effluent water which leaves the basin on an ebb tide, mixes with the surrounding coastal water and returns on subsequent flood tides. This effect has been taken into account in the mathematical model by the inclusion of a ‘pollution-return’ parameter. The analytical approach offers a viable and computationally inexpensive alternative to conventional multi-dimensional pollutant transport simulations and, more importantly, provides an increased understanding of the flushing characteristics of semi-enclosed tidal basins. The efficiency of the tidal flushing can be expressed in terms of the pollution exchange coefficient which measures the proportion of water exchanged with the sea each tidal cycle. To demonstrate the accuracy of the proposed mathematical formulation, analytical water quality predictions are compared against experimental pollution data from a 1:400 scale laboratory model of a generic square harbour. The results demonstrate that the analytical approach provides a simple and robust method of determining the water quality response of well-mixed tidal embayments.     

Water hyacinths as a resource in agriculture and energy production: a literature review

Water hyacinths are becoming a problem in lakes, ponds and waterways in many parts of the world. This paper contains a literature study of different ways to use water hyacinths, mainly in agricultural or alternative energy systems. The literature review indicated that water hyacinths can be rich in nitrogen, up to 3.2% of DM and have a C/N ratio around 15. The water hyacinth can be used as a substrate for compost or biogas production. The sludge from the biogas process contains almost all of the nutrients of the substrate and can be used as a fertiliser. The use of water hyacinth compost on different crops has resulted in improved yields. The high protein content makes the water hyacinth possible to use as fodder for cows, goats, sheep and chickens. Water hyacinth, due to its abundant growth and high concentrations of nutrients, has a great potential as fertiliser for the nutrient deficient soils of Africa and as feed for livestock. Applying the water hyacinths directly without any other processing than sun drying, seems to be the best alternative in small-scale use due to the relatively small losses of nutrients and workload required. To meet the ever-growing energy demand, biogas production could be one option but it requires investments and technological skills that would impose great problems in developing countries where the water hyacinth is often found. Composting as an alternative treatment has the advantage of a product that is easy to work into the soil compared with dried water hyacinths, because of the decomposed structure. Harvesting and transport of water hyacinths can be conducted manually on a small scale and does not require a new harvesting technique to be introduced. Transporting of fresh water hyacinths means, if used as fertiliser in amounts large enough to enhance or effect crop growth, an unreasonably large labour requirement. Based on the labour need and the limited access to technology, using dried water hyacinths, as green manure is a feasible alternative in many developing countries.     

Leaching properties of stabilised/solidified cement-admixtures-sewage sludges systems

One of the main objectives of this work is to present an effective alternative for the final destination of sludge from urban waste water treatment plants by its use as a component of mortar or concrete. A binding and stabilizing matrix of sludge-cement and sludge-cement-coal fly-ash was investigated and the effects of various percentages of waste and binder, on the behavior of sludge in the system are presented. Assessment of the environmental quality of the final product and the consequent guarantee of its use in the building industry demand that it meets a number of requisites, one of which is that the effluents extracted by water action should be contamination-free, or at least that the concentration of contaminants should be below certain pre-set limits. For this a number of leaching tests must be carried out, such as the Netherlands Leaching Test .     

Removal of ammonium and phosphates from aqueous solutions by biochar produced from agricultural waste

The concern about protecting water quantity and quality is one of the most severe challenges of the twenty-first century since the demand for water resources grows as the population and its needs grow. Additionally, and as expected, most human activities produce wastewater containing undesirable contaminants. On the other hand, the generation of agricultural waste and its inappropriate disposal causes further problems. Current wastewater treatment methods involve a combination of physical and chemical processes, technologies, and operations to remove pollutants from effluents; adsorption is an excellent example of an effective method for wastewater treatment, and biochar is currently one of the most valuable adsorbents. This review focuses on new research about applying biochar produced from agricultural waste as a low-cost and environmentally friendly method for removing ammonium and phosphates from aqueous solutions.

     

Effectiveness of novel and traditional treatments on the performance of incinerator bottom ash waste

Management of natural aggregate resources has become one of the most important challenges in construction, especially for high demand applications such as roads. Incinerator bottom ash (IBA), which is produced from burning domestic waste, has been considered a useful solution to the shortage of natural resources. In this research, IBA was mixed with limestone to produce an acceptable blend for use as a road foundation layer. Novel and traditional additives were adopted to improve the mechanical properties of IBA blends. The study focused on the treatment effect of additives on the mechanical characteristics of IBA blends under monotonic and cyclic triaxial stresses. The investigation evaluated fundamental material properties, including resilient modulus, initial Young's modulus and Poisson's ratio. Two nonlinear empirical models were adopted to depict the experimental resilient modulus results of the IBA blends. An approach has been proposed to predict realistic and representative values of resilient modulus for the material. In addition, a new relationship has been established between Young's modulus, resilient modulus and Poisson's ratio. Triaxial test results revealed that additives are more efficient with the control limestone blend than with the IBA blends. Novel additives, such as enzyme I and silica fume, produced a noticeable improvement in IBA properties in comparison to traditional additives.     

The first commercial supercritical water oxidation sludge processing plant

Final disposal of sludge continues to be one of the more pressing problems for the wastewater treatment industry. Present regulations for municipal sludge have favored beneficial use, primarily in land application. However, several agencies and entities have warned of potential health risks associated with these methods. Hydrothermal oxidation provides an alternative method that addresses the health concerns associated with sludge disposal by completely converting all organic matter in the sludge to carbon dioxide, water, and other innocuous materials. A hydrothermal oxidation system using HydroProcessing, L.L.C.'s HydroSolids process has been installed at Harlingen, Texas to process up to 9.8 dry tons per day of sludge. Based on a literature review, this system is the largest hydrothermal oxidation system in the world, and the only one built specifically to process a sludge. Start up of Unit 1 of two units of the HTO system began in April 2001. Early results have indicated COD conversion rates in excess of 99.9%. Harlingen Waterworks System estimates that the HydroSolids system will cost less than other alternatives such as autothermal thermophilic aerobic digestion and more traditional forms of digestion that still require dewatering and final disposal. The Waterworks intends to generate income from the sale of energy in the form of hot water and the use of carbon dioxide from the HydroSolids process for neutralization of high pH industrial effluent. The Waterworks also expects to generate income from the treatment of septage and grease trap wastes.     

Analytical Modelling Of Inorganic Contaminants In Leachate

The need for estimating the contaminant concentration of leachates from landfills has rapidly become important because of the increased demand for landfilling, causing serious pollution of water bodies in some places. The present study examines the movement of inorganics from waste into leachate in the course of time. Inorganics are discussed in two groups according to their solubilities in water. The first group of inorganics dissolve immediately in water (i.e. at time t = 0). The inorganic compounds of the second group transfer into water over a longer period of time. The mathematical model is based on a porous and well-mixed medium, and on assumptions of dissolution/dilution and mass transfer according to their infiltration rate. The agreement between theoretical and experimental results from laboratory and literature are investigated. After experimental verification, some mathematical relationships to predict the mass transfer coefficient (k) and maximum concentration (C_max) were also investigated.     

An Updated Cost Study for Enhanced Sludge Washing of Radioactive Waste

This article updates previous cost savings studies conducted to evaluate the use of enhanced sludge washing (ESW) of high‐level radioactive waste at the United States Department of Energy Hanford Site. The cost savings estimate was updated using stochastic analysis based on new information from the Independent Review of Hanford High Level Waste Volume and the more recent Tank Waste Remediation System Operation and Utilization Plan. It is estimated that implementation of ESW in the tank waste remediation system (TWRS) at the Hanford Site can save approximately $4.8 billion compared to the use of an alternative, simpler water wash. The simpler water wash dissolution was found to be 85 percent as effective as the ESW dissolution. Further, the updated remediation cost estimate of $4.8 billion savings is uncertain only within ±$1.6 billion at the 95 percent confidence interval. © 2002 Wiley Periodicals, Inc.     

Long-term consequences of non-intentional flows of substances: Modelling non-intentional flows of lead in the Dutch economic system and evaluating their environmental consequences

Substances may enter the economy and the environment through both intentional and non-intentional flows. These non-intentional flows, including the occurrence of substances as pollutants in mixed primary resources (metal ores, phosphate ores and fossil fuels) and their presence in re-used waste streams from intentional use may have environmental and economic consequences in terms of pollution and resource availability. On the one hand, these non-intentional flows may cause pollution problems. On the other hand, these flows have the potential to be a secondary source of substances.This article aims to quantify and model the non-intentional flows of lead, to evaluate their long-term environmental consequences, and compare these consequences to those of the intentional flows of lead. To meet this goal, the model combines all the sources of non-intentional flows of lead within one model, which also includes the intentional flows.Application of the model shows that the non-intentional flows of lead related to waste streams associated with intentional use are decreasing over time, due to the increased attention given to waste management. However, as contaminants in mixed primary resources application, lead flows are increasing as demand for these applications is increasing.     

Groundwater Modeling of a Complex Hydrologic System in South Carolina Through the Use of Analytic Elements

The objective of this study is to evaluate the use of the Analytical Element Method (AEM) toward multiobjective, multiscale, ongoing modeling needs at complex hydrologic sites such as those managed by the US Department of Energy. This method presents several advantages over the traditional numerical methods that include absence of grid, natural incorporation of hydrologic features, and generation of an exact solution at every point in a flow field. The AEM with its semi-analytical formulation is particularly efficient in addressing what-if scenarios, the resolution of boundary conditions, and the incorporation of new data all of which are important aspects of remediation efforts in complex sites. Our model accounted for important hydrologic features in an area of the Savannah River Site, South Carolina that included river branches, artificial surface basins, monitoring wells, and the existence of heterogeneities. Our simulated heads were found to be in excellent agreement with the measured heads, with over 90% of the wells exhibiting a maximum discrepancy of less than 10 ft. The AEM was found to be a very efficient and fast method for the analysis of a flow field even when a limited number of elements was considered. The AEM was seen to lead to better physical understanding and resolution of the critical components of a groundwater system and it can offer significant advantages in using models to guide site characterization and remediation efforts.     

Weathering of Oils at Sea: Model/Field Data Comparisons

The SINTEF Oil Weathering Model (OWM) has been extensively tested with results from full-scale field trials with experimental oil slicks in the Norwegian NOFO Sea trials in 1994 and 1995 and the AEA 1997 trials in UK. The comparisons between oil weathering values predicted by the model and ground-truth obtained from the field trials are presented and discussed. Good laboratory weathering data of the specific oil as input to the model is essential for obtaining reliable weathering predictions. Predictions provided by the SINTEF-OWM enable oil spill personnel to estimate the most appropriate “window of opportunity” for use of chemical dispersants under various spill situations. Pre-spill scenario analysis with the SINTEF Oil Spill Contingency and Response (OSCAR) model system, in which the SINTEF-OWM is one of several components, has become an important part of contingency plans as well as contingency training of oil spill personnel at refineries, oil terminals and offshore installations in Norway.     

Leachate recirculation in a landfill: some insights obtained from the development of a simple 1-D model

The re-introduction of leachate back into the waste can play an important part in landfill management. It can encourage biodegradation by raising the water content and transporting bacteria, nutrients and waste products. It also enables leachate to be stored within the body of the landfill, for example to help minimise temporal variations in the load on a leachate treatment plant. It is helpful for a landfill operator to be able to estimate the rate at which the landfill can accept leachate (the maximum infiltration or injection rate), the storage capacity of the landfill and the leachate retention time. This paper discusses some of the insights obtained from the development and application of a simple conceptual model of leachate recirculation that can be used to estimate key parameter values on the basis of the hydraulic properties of the waste. The model is described, partly validated against a more rigorous numerical analysis, and then used to interpret data obtained from field tests on a real site. The shortcomings of the model in its current form are discussed, and suggestions are made as to how these might be addressed in the context of developing the model as a design tool.