Two three dimensional Eulerian air quality models, PMCAMx and UAM-AERO are used to predict the concentrations of various pollutants in the Greater Athens Area (GAA) during the episode of June 22-26, 2003. The predicted levels of gases and aerosol pollutants are compared with measured concentrations...

To achieve recycling of waste gypsum boards (CaSO4), production of calcium sulfide by reductive decomposition of CaSO4 was investigated and the decomposition product of CaS was used as a sulfuration agent in the treatment of nickel-containing simulated wastewater. At the end of the experiment...

The traditional approach to urban water management is primarily based on a supply-oriented approach, where water follows a one-way path from supply to a single use, treatment and then discharged to the environment. The wide acknowledgement of the need to shift towards more sustainable practices has...

It is difficult for decision-makers to evaluate the impact of their territorial policies. Aspects to be considered in this evaluation include those relating to humans, environment protection and industry development. Two reasons explain the difficulty: decision-makers cannot specialise in all...

As part of an effort to understand the water quality dynamics in the Kouris Dam and the impact of possible management strategies, the present study assessed the transport process of atrazine in this reservoir and the effects of bottom and surface withdrawal schemes. The 2- D laterally averaged CE...

There is an emerging need to support water and food policy and decision making at the global and national levels. A systematic tool that is capable of analyzing water-food relationships with high spatial resolutions would be very useful. A GEPIC model has recently been developed by integrating a...

Decision support systems (DSS) are used to aid at solid waste management, a tedious problem with many technical, economic and social constraints. The main DSS available are briefly presented and the development of a novel system, ReFlows, is described. The novelty of the developed DSS consists of...

The spatial resolution of General Circulation Models (GCMs) is too coarse to represent regional climate changes at the scales required for environmental impact assessment. Therefore, downscaling of precipitation and temperature has to be carried out from the GCM grids to smaller scales of a few...

A bench-scale biofiltration system was developed to evaluate the NOx removal efficiency under high oxygen concentration. The system had been running for 120 days and kept on a steady NOx removal rate above 80%. A stable NOx removal with an efficiency of more than 80% from the gas phase can be...

A simple model is presented for the dynamic calculation of the sludge blanket height and concentrations of suspended solids (diluted, sludge blanket and return sludge) in circular secondary settling tanks. The model combines a mass balance equation with three empirical equations, which account for...

The importance of the development and application of groundwater simulation mathematical models in the protection of aquifer systems is nowadays recognised as an undisputable fact. In this paper a mathematical model that was developed in order to simulate the operation of the Upper Anthemountas...

A 3D hydrodynamic/pollutant transport model was used to simulate the currents and pollutant transport in coastal areas. The bathymetric and shoreline data was provided to the model via a GIS module that operates in the ArcView GIS environment. The module is efficient and capable of generating...

In order to study the erodibility characteristics of some calcareous soils from Central Greece, the instability of aggregates of 2.0-4.7 mm in water was studied. Soil loss experiments were also conducted in the laboratory using a rain simulator where soil loss was measured and the soils’ attitude...

This paper investigates the hydrological effects of specific land use changes in a catchment of the river Pinios in Thessaly (Ali Efenti catchment), through the application of the Soil and Water Assessment Tool (SWAT) on a monthly time step. The model's calibration efficiency is verified by...

The scope of this paper is the evaluation of wastewater reuse quality criteria and treatment specifications, appropriate to Greek conditions. The parameters that affect wastewater reuse criteria were taken into consideration, concerning among others reuse priorities, available treatment plants and...

Laboratory column tests were conducted to study the efficiency of lignite fly ash barriers in removing heavy metal ions, such as Fe, Zn, Mn, Ni, Cd, Co, Al and Cu, present in high concentrations in acidic leachates produced in mining and waste disposal sites. The experimental configuration comprised...

The problem of the passive contaminant spreading in a steady viscous fluid stream is discussed while the admixture's dissipation and diffusion are taken into account. The channel is assumed to be a horizontal plane, curvilinear and quite lengthy, so that the ratio of the stream width to its length...

A multi-layered three-dimensional hydrodynamic model has been developed to provide flow fields and water level changes in Hamilton Harbour. The field data collected in Hamilton Harbour during 1990 & 1991 field seasons was used for model verification. The simulated currents were compared with current...

The development of a conceptual site model (CSM) is an invaluable tool used for assessing and planning remedial actions at a contaminated site. The CSM incorporates site-specific, hydrogeologic and geochemical information to identify contaminants of concern, sources of pollution, environmental...

A risk-based decision analysis methodology is presented, that can be used as a water policy tool in the design of economic incentive instruments, under conditions of uncertainty. A contaminated groundwater resource system with unknown hydrogeological parameters is used as a case study. The polluter...

Accumulation of airborne pollutants in vegetation is an important initial step in the uptake process of the terrestrial food web, providing direct and indirect routes by which biota and, eventually, humans are exposed to chemicals. A set of algorithms for estimating atmospheric pollutant...

Pump-and-treat (P&T) is one of the most common methods for remediation of groundwater contaminated by hazardous wastes. However, this method suffers from serious disadvantages, due a series of subsurface processes. Using experimental data and mathematical model simulations, the role of sorption/...

This work illustrates the use and some related results of Artificial Neural Networks (ANNs) for data quality control of environmental time series and for reconstruction of missing data. ANNs are applied to the following problems: i) short and medium-term predicting of air pollutant concentrations in...

Aeration is one of the most common stages in the liquid waste clarification process. Most aeration tanks are equipped with aeration devices that inject oxygen to enhance the biodegradation of the liquid waste. In this work an aeration process is simulated, where the air is injected from the bottom...

Drainage management problems are usually very hard to simulate due to the uncertainty of the hydraulic parameters involved. Fuzzy analysis is one of the available tools that can be used for such problems, involving uncertain data. A fuzzy analysis approach usually involves the consideration of...