Underground Water Contamination Research Articles

Deslocamento miscível de cátions básicos provenientes da água residuária de mandioca em colunas de solo

Objetivou-se, com este estudo, determinar os fatores de retardamento e os coeficientes de dispersão-difusão dos íons potássio, sódio, cálcio e magnésio, presentes na água residuária de fecularias ou manipueira, e simular as concentrações residentes em colunas de solos de 160 cm, pelo período de 5 h. Os ensaios foram realizados em laboratório utilizando-se colunas de percolação preenchidas com amostras de Neossolo Quartzarênico órtico espódico (RQo), Latossolo Amarelo distrófico típico (LAd) e Latossolo Vermelho Amarelo distrófico típico (LVAd). A concentração dos íons no efluente foram analisados empregando-se a metodologia de deslocamento de fluidos miscíveis. Os valores mais elevados dos fatores de retardamento ocorreram no LVAd, indicando maior retenção dos íons potássio, sódio, cálcio e magnésio nesse solo. Os valores dos coeficientes dispersivos-difusivos decresceram no sentido do RQo para o LVAd, sendo que o maior valor ocorreu no RQo para o íon potássio, e o menor no LVAd, para o íon cálcio. A simulação para um período de aplicação da manipueira de 5 h, mostrou pequeno avanço dos íons na coluna do LVAd, em comparação com RQo e LAd alertando, assim, para os perigos de contaminação de águas subterrâneas ao se aplicar a manipueira nesses solos.

NITROGEN REQUIREMENTS OF DRIP IRRIGATED STRAWBERRIES GROWN IN SUBTROPICAL ENVIRONMENTS

NITROGEN REQUIREMENTS OF DRIP IRRIGATED STRAWBERRIES GROWN IN SUBTROPICAL ENVIRONMENTS

Sorption of the Herbicide Terbumeton and its Metabolites onto Soils. Influence of Copper(II)

Environmental Context.Agrochemicals have contributed greatly to modern agriculture, allowing better yields and lower costs. However, their extensive use has led to frequent contamination of underground and surface water. A better knowledge of the fate of pesticides from the sprayer to the water that would take into account the diversity of the physical and chemical properties of the various molecules and environmental conditions should help in the challenge of protecting and restoring natural water quality. Abstract.The intensive use of terbumeton (N-(1,1-dimethyl)-N′-ethyl-6-methoxy-1,3,5-triazine-2,4-diamine) has resulted in its widespread presence, together with its main metabolites, in surface- and groundwater. To estimate the fate of these compounds, their adsorption and desorption properties were studied in vineyard soils. The values of the organic carbon normalized adsorption coefficient (KOC) for terbumeton (34.6 and 39.2 L g−1) were significantly higher than those of its metabolites (between 6.8 and 21.1 L g−1). Terbumeton exhibited a higher adsorption capacity and a lower desorption potential as compared with the metabolites. An important hysteresis was observed in all cases. The Freundlich isotherms exhibited a linear shape, which was interpreted as non-specific interaction. The influence of copper(II), a ubiquitous metal cation in vineyard soils, on pesticide sorption was also studied. Copper significantly decreased the amount of adsorbed terbumeton when present in a high concentration (2 ×10−4 M).

Removal properties of arsenic compounds with synthetic hydrotalcite compounds

The contamination of underground water with inorganic arsenic compounds has caused serious problems, particularly in developing countries. For water containing low-level arsenic compounds, an adsorption process may be more effective than other processes such as RO membrane and precipitation. In this study, the removal performance for arsenic compounds was examined with synthetic hydrotalcite (HTAL) compounds as an adsorbent process from the following viewpoints: the adsorption capacity, adsorption isotherm, the effects of pH and co-existing anions. The HTAL-Cl, which contains Cl− ions as an intercalate, showed very high adsorption capacity in the neutral pH region. The maximum adsorption capacity was 105 mg-As(V) g−1. The adsorption isotherm was approximated by the following modified Langmuir equation:The equation suggests that one mol of As(V) occupies two adsorption sites of HTAL-Cl, and the experimental result indicated that 2.64 mol of Cl− ions in the HTAL-Cl were substituted with one mol of As(V). The interfering effects of co-existing anions were relatively low, and the magnitude of the effects was observed in the order of HCO3− > HPO42− > SO42− > Cl−.

Chemical Compatibility of Lime Stabilized Indian Red Earth as Liner Material

Geotechnical liners are widely used to contain leachate generated within landfills and minimize the risk of sub-surface and underground water contamination. In this study, an attempt has been made to utilize locally available soil red earth as liner material. The collected red earth contains mostly quartz and kaolinitic minerals. Studies have shown that bentonite content higher than 20% by weight is not usually required. This study aims to assess the red earth with 20% by weight of bentonite as liner material. Further, the studies are being carried out to improve the amended material by stabilizing the mixture with 1% by weight of lime. The relative merits of these materials under different physico-chemical environments are studied. The assessment of the liner material is based on their basic and geotechnical properties. The studies reveal that the geotechnical properties of red earth with 20% by weight bentonite stabilized with 1% by weight of lime enhanced, particularly after curing for sufficient period. The pore fluids such as HCl and CCl 4 increased volume change. The hydraulic conductivity of soils, which increased on treating with lime initially, decreased with curing. However, the hydraulic conductivity of stabilized soil increased in the presence of HCl and CCl 4 . The strength of stabilized soil is affected with the fluids NaCl and HCl solutions.

Environmental diagnosis of risk areas related to gas stations

Studies were carried out on the localization and mapping of gas stations in the urban area of São Carlos city, for an environmental diagnosis related to soil, surface water and underground water contamination resulting from likely leaking in fuel underground storage tanks. Considering that a provision of legal restriction makes it possible that most of public areas are not located in gas station areas of potential risk, these information are useful for the development of programs designed to reduce risks to public safety and health and of the soil, surface water and underground water contamination.

Radionuclide contamination of underground water and soils near the epicentral zone of cratering explosion at the Semipalatinsk Test Site

The investigation wells for a control of the underground water contamination were bored after the cratering explosions at the Semipalatinsk Test Site, now they are restored partially. The analysis of the retrospective information of the Institute of Global Climate & Ecology (Moscow, Russia) give a possibility to choose wells and terrains for the successful study of radionuclide migration with the underground water. The epicentral zone, the crater and the territory with radius 1,5 km around the explosion “1003 were investigated under the ISTC project K-810. Underground water and soil samples were taken at the two expeditions of 2003. The chemical extraction methods taking into account the water mineral composition, gamma-spectrum methods, methods of liquid scintillation spectrometry and methods of alfa-spectrometry were used. The modern radionuclide content (3 H, 90 Sr, 137 Cs, 239+240 Pu, 241 Am etc.) of the underground water is presented and compared with a radionuclide content of soils around crater. The retrospective information has been added by these modern data. The vertical radionuclide distrioin soils is presented.

Mutagenicity assessment of effluents from textile/dye industries of Sanganer, Jaipur (India): a case study

Sanganer town, district Jaipur (Rajasthan, India), is famous worldwide for its dyeing and printing industries. There are about 400 industries involved in textile printing processes, which discharge effluents into nearby ponds and drains, without any treatment. These effluents contain highly toxic dyes, bleaching agents, salts, acids, and alkalis. Heavy metals like cadmium, copper, zinc, chromium, and iron are also found in the dye effluents. Textile workers are exposed to such waters with no control over the length and frequency of exposure. Further, as the untreated effluents are discharged into the environment they can cause severe contamination of surface and underground water. Environmental pollution caused by such textile effluents results in adverse effects on flora, fauna, and the general health of not only the textile workers, but also the residents of Sanganer town. Therefore, to assess the possible genotoxic health risk and environmental genotoxicity due to the textile industry effluents, this study was carried out using the Ames Salmonella/microsome mutagenicity assay. The results clearly indicate that the effluents and the surface water of Amani Shah drainage have high mutagenic activity. Further, the drainage water and the dry bed of the drainage (during summer months) are not fit for agricultural or other recreational purposes. A low level of mutagenicity in the underground water of Sanganer again emphasizes the grave pollution problem existing in the area. Multiple post hoc comparison tests (LSD, Tukey's) were used for comparison of sample site, dose, and length of exposure. Quadratic Model was found to adequately fit the observed data.

Engrais minéraux

Mineral fertilizers are intended to correct soil deficiencies in inorganic nutrients, especially nitrogen, but also phosphorus and potassium. The most common are the so-called NPK that typically consist of ammonium nitrate, phosphorus and potassium salts. Intentional ingestion of a concentrated liquid fertilizer can result in severe poisoning because of the high potassium concentration of these formulations. Except for a few cases of dermatitis and dust-induced mucosal irritation, very few adverse effects have been reported in the occupational setting. Some fertilizers that contain calcium cyanamide can cause an antabuse reaction. Excessive use of mineral fertilizers lead to the contamination of underground water by nitrates, non volatile and highly hydrosoluble compounds that are subsequently found in drinking water. Nitrates have been claimed to cause methaemoglobinemia in newborns and cancer in the general population, especially of digestive tract. Recent data on their disposition as well as results of experimental and epidemiological studies conducted during the past 30 years show that their toxicity had been largely overestimated. Methaemoglobinemia in the newborn is actually related to a microbiological contamination of the drinking water. No causal link between long-term consumption of nitrate-rich drinking water and cancers in the general population could be demonstrated. Several collective expert reports concluded on the safety of nitrates and the inadequacy of current regulations. Recent in vitro investigations indicate that a physiological role of nitrates in humans as biocides is likely.

Acidification and release of heavy metals in dredged sediments

The oxidation of iron sulphides in dredged sediments can be a source of long-term contamination of surface and underground water. The adverse effects are related to a decrease in the ability of soil to retain heavy metals, which is caused by acidification. Laboratory tests were conducted, and pH variations and consequent release of heavy metals, especially Zn, Cu, and Pb, into the solution were monitored over time. The rate of pyrite oxidation was determined based on the sulphate production rate, through the stoichiometry of the oxidation reaction. Samples of sediments from the Jacarepaguá lagoon complex, State of Rio de Janeiro, were dried and oxidized over a period of 10 months. During this period the pH fell from 6.9 to 3.3, with oxidation of approximately 20% of the sulphur present in the form of iron sulphide, and 45% of the Zn, 15% of the Pb, and 5% of the Cu contained in the material were released. The oxidation rate at the initial stages was of the order of 1.0 × 10–4 g(O2)·h–1, decreasing to 1.0 × 10–5 g(O2)·h–1 during the test. This study presents the laboratory methodology developed for determining the oxidation rate in a system where the oxygen consumption is governed not only by the pyrite oxidation, but also by the organic matter. In these experiments, a key measure of intrinsic oxidation rate (IOR) is the oxidation rate where oxygen is freely available at normal atmospheric concentration. By comparing the values obtained for the dredged material with the results of the IOR of mining waste materials reported in the literature, it was observed that the oxidation rates of the iron sulphide formed in the Jacarepaguá lagoon environment were one to two orders of magnitude higher than those of mineral iron sulphides from coal wastes. This behavior can be explained considering that the iron sulphides in dredged materials are freshly formed and have more specific surface area exposed to air than the iron sulphide mineral in mining wastes.Key words: sediments, dredging, sulphides, oxidation, acidification, heavy metals.

Implementation of ISO-14000 Standards In Routine Environmental Management of Oil And Gas Fields By Means of GIS And Remote Sensing

Abstract All industrialized countries face the challenge to combine long term, low cost energy supply and continuous reduction of the environmental impact. Therefore the strategic target of the HSE standards is the sustainable and environmentally sound development of the Earth's energy resources. The main goal of our research is the development of a new environmental management methodology supported by software tools for implementation of the ISO-14000 standards in oil and gas operations. On one hand, this methodology has to be generic; on the other hand, the proposed methods of environmental impact assessment must be applicable for each specific situation. We have reinterpreted the ISO environmental monitoring model in terms of remote sensing survey and GIS models. Besides storage of the scalable earth surface and underground information, the methodology and suggested software tools allow for the modelling of the interaction between engineering objects and the environment during full life cycle of oil and gas fields starting from their exploration until their abandonment. The remote sensing methods reviewed in this article, as well as the suggested methodology, can be applied for a wide range of targets in different regions. Some examples are the monitoring of pipelines in the North Sea or Mexican Gulf, control of pipeline security or vegetation degradation in tropical countries, as well as monitoring of oil operations in remote Arctic locations. Introduction Protection of the environment, the health and safety of citizens, and sustainable and economically effective exploitation of domestic natural resources are key issues in many industrially developed countries. The international Health, Safety and Environment (HSE) regulations have been finalized in the ISO-14000 standards. The United Nations Conference on Environment and Sustainable Development (UNCED), as well as the International Expert Meeting on Environmental Practices in Offshore Oil and Gas Activities (Reference Technical Background document, 1997) have emphasized the significance of implementation of the international environmental standards and innovation of environmental monitoring systems in oil and gas operations. However, oilfield oriented database management (or monitoring) systems, currently available on the market, contain mainly (or only) exploration and production (E&P) inventory databases. They do not include any environment, health or safety related parameters or functions. Moreover, in spite of the tremendous progress in information technologies (such as GIS, remote sensing, Internet), they are hardly used either in oilfield environmental management systems or in E&P databases. Objectives In the last few years, there have been numerous cases of largescale environmental damage caused by oil and gas production. They involve contamination of surface water, underground water and marine seawater, agricultural soils, air pollution, etc. In many countries, extensive development of the oil industry has resulted in degradation of other natural resources, including deforestation of the surroundings of exploration and production facilities. Thus, oil and gas exploitation needs to improve on the point of environmental side effects. Unfortunately, there are no broadly available software tools for long-term comprehensive environmental monitoring. Therefore, TNO-NITG has initiated a new project aimed at the development of an Integrated Oil and Gas Environmental Monitoring and Management System (IOGEMMS).

Complex Model to Study Long Term Environmental Tritium Behavior

ABSTRACTTo assess long-term environmental safety of a tritium facility, prediction of consequences of potential tritium releases in the environment is needed both during routine operations and in case of accidents. Modeling is the only method to obtain such assessment without any environmental contamination.The current paper describes the TRIEF model designed to assess consequences of long-term atmospheric tritium emission for such environmental compartments as atmosphere, soil, plants; tritium contamination of ground and underground water is also included. The model takes into account tritium transport among all of the compartments. The model has been successfully validated in model-experiment intercomparison study in framework of the IAEA co-ordinated research programme “BIOMASS” on assessment of environmental contamination from the continuous source of atmospheric tritium release. The experimental data included tritium concentrations in the atmospheric moisture, vegetation, soil and the overlying snow cover. The modelling period was 20 years. Most of the predicted values agreed with observations within experimental uncertainties, which were a factor of 2.The TRIEF model is based on both HTO equilibrium and material balance approach in all the compartments. Average concentrations in atmosphere are calculated by using the Gauss-type model for primary and secondary source. HT and HTO behavior are modeled separately. Both wet and dry deposition of HTO is taken into account in case of HTO emission. HTO concentration in soil moisture is determined by the moisture balance equation. HTO concentration in plant tissue free water and organically bound tritium are estimated as a combination of HTO content in soil moisture and atmospheric humidity. HTO contamination of aquifer is modeled using available finite-differences codes within 12 hydro-geological strata.

Efeito da irrigação inicial na profundidade de lixiviação do herbicida s-metolachlor em diferentes tipos de solos

Muitas vezes a profundidade de lixiviação dos herbicidas aplicados ao solo afeta a seletividade destes às culturas. O objetivo deste trabalho foi estudar a lixiviação do herbicida s-metolachlor em cinco tipos de solos (Podzólico Vermelho-Amarelo, Latossolo Roxo, Latossolo Vermelho-Amarelo, Areia Quartzosa-turfosa e Areia Quartzosa), bem como avaliar o efeito do manejo das primeiras irrigações antes e após a aplicação do herbicida sobre esse processo, por meio de bioensaios, relacionando os resultados encontrados com possíveis efeitos fitotóxicos ocorridos em algumas culturas comerciais. Os experimentos foram realizados em casa de vegetação, utilizando-se colunas de lixiviação, sendo compostos de oito tratamentos, formados da combinação de dois tipos de irrigação inicial (lâmina de irrigação de 25 mm antes ou depois da aplicação do s-metolachlor) com quatro faixas de profundidade de coleta dos solos (0-5, 5-10, 10-15 e 15-20 cm), com cinco tipos de solos. O herbicida s-metolachlor foi pulverizado na dose de 1,92 kg ha-1 em todos os tratamentos, e a planta indicadora utilizada foi o sorgo-granífero (Sorghum bicolor), híbrido BR 304. Observou-se tendência de maior lixiviação e maior disponibilidade do s-metolachlor em todos os solos avaliados quando a irrigação foi realizada após a aplicação do herbicida. Na Areia Quartzosa ocorreu a maior lixiviação e disponibilidade do herbicida. Em todos os solos, o s-metolachlor concentrou-se na camada mais superficial do solo de 0-5 cm. Conclui-se que solos com baixos teor de matéria orgânica e CTC efetiva aumentam a predisposição da ocorrência de efeitos fitotóxicos do s-metolachlor às culturas e a probabilidade de contaminação de águas subterrâneas.

Environment, tourism and land use planning – Riachinho Basin, Brazil

Santana do Riacho County, in Minas Gerais State, Brazil, is located in an area known for its natural beauty. The growth of tourism has been the main economic activity of this area. In order to achieve organized land occupation and self‐sustained development, thematic maps of the physical environment were elaborated. Analysis of the water sources supply and recreation have been completed. The risk of water contamination has increased, caused by the increase of tourism activities in this area, added to by local authorities policy. The analysis of all the thematic maps and of the quality of the water sources supply of the area, lead us to develop proposals for land use planning and zoning, adequate for the local conditions and the vulnerability of the underground water contamination. These issues are important concerning the local development and also land use, caused by the tourism activities.

Contaminação do ambiente aquático por pesticidas. Estudo de caso: águas usadas para consumo humano em Primavera do Leste, Mato Grosso - análise preliminar

A preliminary analyses of the possible contamination of superficial and underground water by the active ingredients of the pesticide products used in the surroundings of the urban area of Primavera do Leste, Mato Grosso, Brazil, was carried out. A description of the study region and of its environmental characteristics, which can favor the contamination of the local aquatic environment, was presented. The EPA screening criteria, the groundwater ubiquity score (GUS) and the criteria proposed by Goss were used to evaluate which pesticides might contaminate the local waters. Among the active ingredients studied, several present risks to the local aquatic environment.

Evaluation of the potential hazard of secondary radioactive contamination of underground water by sewage works

The time dependence of the distribution of the volume activity of radionuclides over ground layers is calculated under chemically equilibrium and hydraulically stationary condition sand under conditions of continuous operation of radioactively hazardous units of sewage works. As initial information, a set of data on the hydrogeological characteristics and physicochemical properties of the sewage-water sediments (SWSs) found at the sewage works of Chechersk and Slavgorod is used. The results of the calculations performed are analyzed, and the data on the egress of radiocesium from the SWSs found in the sludge areas and filtration fields with different bases into underground water are presented.

リサイクリング 資源リサイクリングと環境問題

Resources supply and environmental protection are increasingly becoming matters of global concern. With increased industrial activities worldwide, a possibility for exhaustion of mineral resources as projected from past demands stirred much controversy regarding the future supply of metals. Mass production and mass consumption generate massive quantities of industrial scrap as well as post consumewastes. Mounting public sentiment against construction of new landfill sites necessitates volume reduction of wastes to be disposed. Incineration is an effective way to conserve landfill spaces, but the potential generation of dioxins and underground water contamination by incinerator residues are becoming a growing public concern. Establishment of social systems for waste minimization and promotion of re-use as well as of technology for improving recycling efficiencies are needed for sustainable development. In this article, concerns over mineral resources supply, issues in environmental protection, and the problems and technological developments associated with recycling are summarized.

Optimizing Nitrogen for Improving Yield and Fruit Quality of `Redspur Delicious' Apple

Effects of three times and five rates of urea application on productivity, tree growth, soil nitrate movement, nutrient partitioning, and postharvest fruit quality of `Redspur Delicious' apple on M.7 rootstock over several years were studied. Time of application did not have significant effects on most fruit quality factors or yield. However, significant differences were observed for quality and yield measurements among different quantities of N. Fruit firmness decreased with every increment in N increase. Trees with N at 0.045 kg/tree had lower yield and higher fruit firmness than those with higher quantities of N. Fruit weight and color decreased with each increment increase in the quantity of N. Trees with N at 0.045 and 0.18 kg/tree had significantly better (more red) color and lower fruit N and leaf N than those with higher quantities of N. Bud tissue nutrients were affected by quantity of N application. Fruit from trees with N at <0.18 kg/tree had lower soluble solids. High N increased fruit ethylene and respiration. Nitrogen application affected 2-methyl butyl acetate of fruit. Monitoring nitrate movement through the soil showed that application of N at >0.45 kg/tree, particularly in fall resulted in excess levels of nitrate, increasing the possibility of underground water contamination. Applying N at ≤0.32 kg/tree did not result in excess soil nitrate at 1.52-m depth.

Nitrogen application and underground water contamination in some agricultural soils of South Western Nigeria

The effect of nitrogen fertilizer application on nitrate leaching and contamination of underground and surface waters in a continuously cropped lowland area of South Western Nigeria has indicated a high potential for nitrate leaching.

“In situ” radiation cleaning of underground water contaminated with cyanides - six years of experience

The locality of underground water, contaminated with cyanides, has been successfully cleaned by using the hydraulic barrier method (assembly of pumped wells) since 1986. The average cyanide concentrations in the outflow exceeded 35 m per litre. Contamination had to be eliminated before the discharge into the sewer system. The radiation approach “in situ” i.e. decomposition of cyanides by barrier, was applied and is still being used today. The cyanide concentration was lowered more than one order of magnitude. This process was approved by the Czechoslovak radiation security authorities and further applications of “in Situ” regeneration of underground water contamination is anticipated.