To evaluate the long-term effect of wastewater application on soil physical properties, two treatment sites, close to Taupo and Levin, New Zealand, and non-irrigated control sites were compared. The soil at Taupo was a silt loam and has received wastewater application for 12 years. The soil at Levin is a sand, and has been wastewater irrigated for 22 years. The disposal blocks at both sites had a higher pH, a higher organic matter (OM) content, a lower bulk density, and thus higher total porosity, but a lower macroporosity than the control sites. The disposal block at the Levin site showed a higher hydrophobicity than the control block, which coincided with the higher soil carbon. In contrast, the Taupo soil showed a higher hydrophobicity at the control site, the site with the lower OM content. Long-term wastewater irrigation resulted in a higher aggregate stability, and changes of the total porosity following stress application were lower, suggesting higher internal soil strength. The hydraulic conductivity close to saturation was also higher in the disposal blocks. The soil mechanical strength, as determined by the precompression stress value was, however, slightly lower in the disposal blocks and not correlated with the aggregate stability.

Seven experimental pilot-scale subsurface vertical-flow constructed wetlands were designed to assess the effect of plants [Typha latifolia L. (cattail)], intermittent artificial aeration and the use of polyhedron hollow polypropylene balls (PHPB) as part of the wetland substrate on nutrient removal from eutrophic Jinhe River water in Tianjin, China. During the entire running period, observations indicated that plants played a negligible role in chemical oxygen demand (COD) removal but significantly enhanced ammonia-nitrogen (NH₄-N), nitrate-nitrogen (NO₃-N) total nitrogen (TN), soluble reactive phosphorus (SRP) and total phosphorus (TP) removal. The introduction of intermittent artificial aeration and the presence of PHPB could both improve COD, NH₄-N, TN, SRP and TP removal. Furthermore, aerated wetlands containing PHPB performed best; the following improvements were noted: 10.38 g COD/m² day, 1.34 g NH₄-N/m² day, 1.04 g TN/m² day, 0.07 g SRP/m² day and 0.07 g TP/m² day removal, if compared to non-aerated wetlands without PHPB being presented.

Photodegradation of four pharmaceuticals (i.e. carbamazepine, ibuprofen, ketoprofen and 17α-ethinylestradiol) in aqueous media was studied using a solar light simulator (Xe lamp irradiation) and sunlight experiments. These experiments were carried out in river and seawater and compared to distilled water. The latter was used to evaluate the direct photodegradation pathways. Irradiation time was up to 400 min and 24 days for the solar light simulator and sunlight assays, respectively. Pharmaceutical photodegradation followed a first-order kinetics and their half-lives calculated in every aqueous matrix. Moreover, the sensitizing effect of DOC was evaluated by comparison with the kinetics obtained in distilled waters. Ketoprofen was rapidly transformed via direct photolysis in all the waters under both sunlight (t ₁/₂ = 2.4 min) and simulated solar light simulator test (t ₁/₂ = 0.54 min). Under xenon lamp radiation, ibuprofen and 17α-ethinylestradiol were photodegraded at moderate rate with half-lives from 1 to 5 h. Finally, carbamazepine had the lowest photodegradation rate (t ₁/₂ = 8-39 h) attributable to indirect photodegradation. Indeed, its elimination was strongly dependent on the DOC concentration present in solution. Finally, several ketoprofen photoproducts were identified and plotted against solar light simulator irradiation time. Accordingly, the photodegradation pathway of ketoprofen was postulated.

Pesticides presently being discharged into the aquatic environment are not only toxic but also only partially biodegradable, they are not easily removed by conventional water treatment plants. Air ionization devices using an atmospheric pressure corona discharge process show great promise in improving degradation of chemical and biological contaminants in water purification plants. In order to assess the effectiveness of this air ionization apparatus, laboratory scale degradation experiments were carried out systematically in a bubble column reactor containing a variety of pesticides such as triazines, carbamates, phenyl urea derivates and chlorophenols relative to the addition of humic acid and inorganic chemicals as well as to pH variation. Chemical oxygen demand (COD) decreased with air ionization treatment and the rate of the biological oxygen demand related to this (BOD/COD) showed improved pesticide biodegradability. Changes in water toxicity were monitored by Daphnia- and Luminescence Bacteria tests. This novel water treatment process is shown to be a potent oxidation technique for persistent organic pollutants such as pesticides.

Biomass cogeneration is widely used for district heating applications in central and northern Europe. Biomass trigeneration on the other hand, constitutes an innovative renewable energy application. In this work, an approved United Nations Framework Convention on Climate Change baseline methodology has been extended to allow the examination of biomass trigeneration applications. The methodology is applied to a case study in Greece to investigate various environmental and financial aspects of this type of applications. The results suggest that trigeneration may lead to significant emissions reduction compared to using fossil fuels or even biomass cogeneration and electricity generation. The emissions reduction achieved may be materialized into a considerable revenue stream for the project, if traded through a trading mechanism such as the European Union Greenhouse Gas Emission Trading Scheme. A sensitivity analysis has been performed to compensate for the high volatility of the emission allowances' value and the immaturity of the EU Trading Scheme, which prevent a reliable estimation of the related revenue. The work concludes that emission allowances trading may develop into one of the major revenue streams of biomass trigeneration projects, significantly increasing their financial yield and attractiveness. The impact on the yield is significant even for low future values of emission allowances and could become the main income revenue source of such projects, if emission allowances increase their value substantially. The application of trigeneration for district energy proves to lead to increased environmental and financial benefits compared to the cogeneration or electricity generation cases.

The paper summarizes the results of a study concerning the operation of industrial plants and their effects to the environment. It also addresses, shortly, the consequences to the quality of human life and proposes potential measures that may contribute to the reduction of the negative environmental impacts. The relatively small organized Industrial Area of Alexandroupolis (Greece) is examined as a case study. In particular, the activities of its major industrial facilities are presented and their emissions to the environment are examined. In addition, the socio-economic aspects of the operation of the Industrial Area are studied. The results of the study showed that the operation of the Industrial Area has specific negative effects in the natural environment of the region and in the quality of life of the residents. Methodological and legislative tools, such as control systems for the environmental pollution, the green chemistry, and the environmental management systems, may be employed to assist the prevention and confrontation of environmental problems.

The distribution and geochemical behavior of nonylphenol (NP) in suspended and settling particles were studied in Lake Biwa, Japan. The vertical distribution of the particulate nonylphenol (PNP)/particulate organic carbon (POC) ratio showed a characteristic and hitherto unreported profile. The ratio was low at the surface, increased with depth to the middle layer before reaching a maximum at a depth of 45 or 65 m, and decreased toward the bottom. This profile is thought to have been due to the particulate organic matter (POM) in the lake being either freshly produced or aged POM and because the aged POM has a relatively higher affinity for NP compared to freshly produced POM. This idea was supported by the statistical analysis of physicochemical data (PNP, POC and chlorophyll a) and because the average PNP/POC ratio in the aged POM (2.24 x 10⁻⁵ g/g) was approximately four times higher than that of the freshly produced POM (0.63 x 10⁻⁵ g/g). The settling flux was estimated to be 2.2-6.4 μg/m²/day.

Investigations of vegetation stress along non-paved roads treated with a range of magnesium chloride (MgCl₂) application rates utilized 60 roadside and 79 drainage plots on 15 and 18 roads, respectively. Evaluations were completed of foliar damage, plant health, biotic and abiotic damage incidence and severity, soil and foliar chemistry and other common site and stand characteristics of Pinus contorta, Populus tremuloides, Picea engelmannii, Abies lasiocarpa, and lower elevation plots dominated by shrubs and grasses. High concentrations of soil magnesium and chloride (400-500 ppm), high foliar chloride (2,000-16,000 ppm depending on species) and high incidence of foliar damage were measured in roadside plots along straight road segments in the first 3 to 6.1 m adjacent to treated roads. In drainage plots, where water is channeled off roads, high concentrations of both magnesium and chloride ions and associated foliar damage were measured between 3 and 98 m from the road. High incidence of foliar damage and elevated ion concentrations were not apparent in control plots along non-treated roads. Lodgepole pine appeared to be the most sensitive species, while aspen accumulated the most chloride and exhibited the least amount of damage. Foliar chloride concentrations strongly correlated with percent foliar damage for all species (r = 0.53 to 0.74, p < 0.0001) while the incidence of biotic damages did not correlate well. Positive relationships between foliar chloride and magnesium chloride application rates were strong and can be used to predict foliar concentrations and subsequent damage to roadside trees.

This paper presents the development of a filtered stepwise clustering (FSC) method for facilitating the pump-and-treat (PAT) designs in groundwater remediation programs. To investigate the performances of different remediation strategies, a subsurface model is employed to simulate contaminant transport. Multivariate relationships between decision variables and selected modeling outputs are developed through the FSC method. Based on the developed statistical relationships, a set of possible outcomes for the remediation design can be presented; the solution space has been confined to a narrowed range. The proposed method can aid the PAT design by (a) quickly providing predicted outcomes given different remediation strategies and (b) directly locating the optimum remediation strategy for any outcome. The FSC method is examined through its application to a real-world aquifer remediation case in western Canada. The prediction results can help decision makers to evaluate the remediation design in an explicit way.

Two-year (June 2003-May 2005) precipitation samples were collected from three monitoring sites with similar economy development level in the Yangtze River Delta Region of China to investigate the spatial-temporal variation of inorganic N wet deposition. The results showed that the Yangtze River Delta Region had higher inorganic N wet deposition than the northwestern, northern, or southern China. There was spatial variation of inorganic N wet deposition. The positive relationship between inorganic N deposition and precipitation suggested that rainfall amount might be an important factor influencing the wet deposition of inorganic N. Deposition of inorganic N occurred mainly in the spring and summer season (March-August; 70% of the annual total), which was in accord with seasonal distribution of precipitation. However, a negative logarithmic relation between rainfall and inorganic N concentration in rainwater indicated the dilution effect of rainwater on inorganic N concentration. Distinguished variation of NH₄ ⁺/NO₃ ⁻ ratio in wet deposition existed in the different time scale. NH₄ ⁺/NO₃ ⁻ ratio evidently decreased from 6 in 1980s to 1.2 in 2003/2005 and greatly varied between 0.3 and 9.9 within a year. NH₄ ⁺/NO₃ ⁻ ratio peaked in accordance with nitrogen-fertilizing time during crop growing season. Annual alternate appearance of the ¹⁵N-enriched and ¹⁵N-depleted periods coincided with the temporal variation of NH₄ ⁺/NO₃ ⁻ ratio, which was closely related to the timing of fertilization and seasonal climate changes, suggesting the effect of NH₄ ⁺ sources in the wet deposition.