Groundwater Contamination Research Papers - Academia.edu (original) (raw)

A non-linear least-squares (NLS) method is used without regularization to recover the release history of a groundwater contaminant plume from its current measured spatial distribution. The¯ow system is assumed to be one-dimensional, with the plume originating from a known single site. The solution is found to be very sensitive to noise and to the extent to which the plume is dissipated. Although the NLS method is extremely sensitive to measurement errors for the gradual release scenario, it can resolve the release histories for catastrophic release scenarios reasonably well, even in the presence of moderate measurement errors. A number of synthetic numerical examples are analysed. We ®nd that for catastrophic contaminant releases the NLS method may be an alternative to the Tikhonov regularization approach.

- by Sharon Doty
- •
- Water, Groundwater Contamination, Multidisciplinary, Tropical trees

Delhi is the most densely populated and urbanized city of India. The annual growth rate in population during the last decade (1991-2001) was 3.85%, almost double the national average. Delhi is also a commercial hub, providing employment opportunities and accelerating the pace of urbanization, resulting in a corresponding increase in municipal solid waste (MSW) generation. Presently the inhabitants of Delhi generate about 7000 tonnes/day of MSW, which is projected to rise to 17,000-25,000 tonnes/day by the year 2021. MSW management has remained one of the most neglected areas of the municipal system in Delhi. About 70-80% of generated MSW is collected and the rest remains unattended on streets or in small open dumps. Only 9% of the collected MSW is treated through composting, the only treatment option, and rest is disposed in uncontrolled open landfills at the outskirts of the city. The existing composting plants are unable to operate to their intended treatment capacity due to several operational problems. Therefore, along with residue from the composting process, the majority of MSW is disposed in landfills. In absence of leachate and landfill gas collection systems, these landfills are a major source of groundwater contamination and air pollution (including generation of greenhouse gases). This study describes and evaluates the present state of municipal solid waste management in Delhi. The paper also summarizes the proposed policies and initiatives of the Government of Delhi and the Municipal Corporation of Delhi to improve the existing MSW management system.

Soilless plant growth systems are widely used as a means to save irrigation water and to reduce groundwater contamination. While nutrient concentrations in the growth medium are depleted due to uptake by the plants, salinity and toxic substances accumulate due to transpiration. A theoretical model is suggested, to simulate nutrient uptake by plants grown in soilless cultures with recycled solutions. The model accounts for salinity accumulation with time and plant growth, and its effects on uptake of the different nutrients by means of interaction with Na and Cl ions. The sink term occurs due to uptake by a growing root system. Influx as a function of the ion concentration is according to Michaelis-Menten active mechanisms for K + , NO 3 − -N, NH 4 + -N, PO 4 -P, Ca 2+ , Mg 2+ and SO 4 2− , whose influx parameters are affected by Na and Cl − , but not with time (age). Sodium influx is passive above a critical concentration. Sum of cations-anions concentrations is balanced by Cl − to maintain electro-neutrality of the growth solution. Salinity (by means of Na concentration) suppresses root and leaf growth, which further effect uptake and transpiration. The model accounts for instantaneous transpiration losses, during daytime only and its effect on uptake of nutrients and plant development due to salt accumulation. The model was tested against NO 3 − and K + uptake by plants associated with cumulative transpiration and with different NaCl salinity levels. Deviations from observed K + uptake should be attributed to the salinity tolerance of the plants. In a study with data obtained from published literature, the model indicated that nutrient depletion and salinity buildup might be completely different with fully grown-up plants (that do not grow) and plants that grow with time. Depletion of different nutrients are according to their initial concentration and plant uptake rate, but also affected by their interactions with Na and Cl ions.

- by J. Ben-asher
- •
- Horticulture, Nutrition, Biomathematics, Groundwater Contamination

This is a report on the contamination of an ideal system for tutorial and exemplary purposes.

A large-scale model of virus transport in aquifers is derived using spectral perturbation analysis. The effects of spatial variability in aquifer hydraulic conductivity and virus transport (attachment, detachment, and inactivation) parameters on large-scale virus transport are evaluated. A stochastic mean model of virus transport is developed by linking a simple system of local-scale free-virus transport and attached-virus conservation equations from the current literature with a random-field representation of aquifer and virus transport properties. The resultant mean equations for free and attached viruses are found to differ considerably from the local-scale equations on which they are based and include effects such as a free-virus effective velocity that is a function of aquifer heterogeneity as well as virus transport parameters. Stochastic mean free-virus breakthrough curves are compared with local model output in order to observe the effects of spatial variability on mean one-dimensional virus transport in three-dimensionally heterogeneous porous media. Significant findings from this theoretical analysis include the following: (1) Stochastic model breakthrough occurs earlier than local model breakthrough, and this effect is most pronounced for the least conductive aquifers studied. (2) A high degree of aquifer heterogeneity can lead to virus breakthrough actually preceding that of a conservative tracer. (3) As the mean hydraulic conductivity is increased, the mean model shows less sensitivity to the variance of the natural-logarithm hydraulic conductivity and mean virus diameter. (4) Incorporation of a heterogeneous colloid filtration term results in higher predicted concentrations than a simple first-order adsorption term for a given mean attachment rate. (5) Incorporation of aquifer heterogeneity leads to a greater range of virus diameters for which significant breakthrough occurs. (6) The mean model is more sensitive to the inactivation rate of viruses associated with solid surfaces than to the inactivation rate of viruses in solution.

Groundwater long-term monitoring (LTM) is required to assess the performance of groundwater remediation and human being health risk at post-closure sites where groundwater contaminants are still present. The large number of sampling locations, number of constituents to be monitored, and the frequency of the sampling make the LTM costly, especially since LTM may be required over several decades. An optimization

A preliminary ecological characterisation of an open quarry that had been used for the disposal of pharmaceutical wastes from a factory producing antibiotics was performed. Pharmaceutical wastes and groundwater samples were collected and analysed in order to assess both the bacterial community structure and functioning, and the contamination by organic compounds, including antibiotics. Bacterial abundance measured using the epifluorescence direct

- by Paola Grenni and +1
- •
- Groundwater Contamination, Environmental Sciences, Waste Disposal, Ground Water

The paper is based on 237 chemical analysis of groundwater, where the determination of magnesium origin in groundwatersof northeastern Bosnia were performed. The determination of magnesium origin in groundwaterswere carried through on the basis of Mandel & Shiftan classification. Based on the results, a distribution map of Mg 2+ ions in groundwaters in northeastern Bosnia were drafted.

- by Dado Srkalovic
- •
- Geology, Hydrogeology, Chemistry, Groundwater

High rates of nutrient loading from agricultural and urban development have resulted in surface water eutrophication and groundwater contamination in regions of Ontario. In Lake Simcoe (Ontario, Canada), anthropogenic nutrient contributions have contributed to increased algal growth, low hypolimnetic oxygen concentrations, and impaired fish reproduction. An ambitious programme has been initiated to reduce phosphorus loads to the lake, aiming to achieve at least a 40% reduction in phosphorus loads by 2045. Achievement of this target necessitates effective remediation strategies, which will rely upon an improved understanding of controls on nutrient export from tributaries of Lake Simcoe as well as improved understanding of the importance of phosphorus cycling within the lake. In this paper, we describe a new model structure for the integrated dynamic and process-based model INCA-P, which allows fully-distributed applications, suited to branched river networks. We demonstrate application of this model to the Black River, a tributary of Lake Simcoe, and use INCA-P to simulate the fluxes of P entering the lake system, apportion phosphorus among different sources in the catchment, and explore future scenarios of land-use change and nutrient management to identify high priority sites for implementation of watershed best management practises.

- by S. Oni
- •
- Groundwater Contamination, Environmental Monitoring, Rivers, Eutrophication

Key attributes of the source zone and the expanding dissolved plume at a trichloroethene (TCE) site in Australia were evaluated using trends in groundwater monitoring data along with data from on-line volatile organic compound (VOC) samplers and passive flux meters (PFMs) deployed in selected wells. These data indicate that: (1) residual TCE source mass in the saturated zone, estimated using two innovative techniques, is small (∼ 10 kg), which is also reflected in small source mass discharge (∼ 3 g/day); (2) the plume is disconnecting, based on TCE concentration contours and TCE fluxes in wells along a longitudinal transect; (3) there is minimal biodegradation, based on TCE mass discharge of ∼ 6 g/day at a plume control plane ∼ 175 m from source, which is also consistent with aerobic geochemical conditions observed in the plume; and (4) residual TCE in the vadose zone provides episodic inputs of TCE mass to the plume during infiltration/recharge events. TCE flux data also suggest that the small residual TCE source mass is present in the low-permeability zones, thus making source treatment difficult. Our analysis, based on a synthesis of the archived data and new data, suggests that source treatment is unwarranted, and that containment of the large TCE plume (∼ 1.2 km long, ∼ 0.3 km wide; 17 m deep; ∼ 2000-2500 kg TCE mass) or institutional controls, along with a long-term flux monitoring program, might be necessary. The flux-based site management approach outlined in this paper provides a novel way of looking beyond the complexities of groundwater contamination in heterogeneous domains, to make intelligent and informed site decisions based on strategic measurement of the appropriate metrics.

- by Ravi Naidu
- •
- Australia, Groundwater Contamination, Multidisciplinary, Contaminant hydrology

Drinking Groundwater Contamination a b s t r a c t

- by Erik Arvin and +2
- •
- Water, Water quality, Groundwater, Fluorescence
- by Elango L
- •
- Hydrogeology, Environmetal Earth Science, Groundwater Contamination, Water Pollution

The current study includes applying 2D Azimuthal resistivity imaging using Wenner configuration in the area which located in Babylon, between longitudes (44˚25' 2"-44˚25' 5.3") and latitudes (32˚27' 12.8"-32˚27' 15.5"). ABEM Terrameter LS used for data collection. The survey design based on choosing the electrode configuration taking into account available information about the site and the advantages of the ERI technique. 2D electrical resistivity imaging sections have been obtained. The data analysis comprises of 2D inversions using the RES2DINV software. The measurements conducted with total length 80 meters to give the possibility depth to study surface changes in values of resistivity and to determine the direction of subsurface flow for contaminated water along 4 tracks at 45°. It was noted that the major quantitative of contaminated water moving toward the southwest , while it is found that there isn't any movement in other direction. It is found that 2D Azimuthal resistivity imaging is an effective tool for detecting the movement direction of groundwater contamination.

Herbicide groundwater pollution is an environmental problem in Northern Italy.

- by Giuseppe Giuliano
- •
- Groundwater, Groundwater Contamination, Agriculture, European Union

Hazaribagh is a densely populated area of Dhaka city where the main leather-tanning zone of Bangladesh is situated. About 185 tanneries have been operating their activities on an area of 4 km2, processing 220 metric tons of hide a day and... more

The behavior of As in the subsurface environment was examined along a transect of groundwater monitoring wells at a Superfund site, where enhanced reductive dechlorination (ERD) is being used for the remediation of groundwater contaminated with chlorinated solvents. The transect was installed parallel to the groundwater flow direction through the treatment area. The ERD technology involves the injection of organic C (OC) to stimulate in situ microbial dechlorination processes. A secondary effect of the ERD treatment at this site, however, is the mobilization of As, as well as Fe and Mn. The concentrations of these elements are low in groundwater collected upgradient of the ERD treatment area, indicating that, in the absence of the injected OC, the As that occurs naturally in the sediment is relatively immobile. Batch experiments conducted using sediments from the site inoculated with an Fe(III)-and As(V)-reducing bacterium and amended with lactate resulted in mobilization of As, Fe and Mn, suggesting that As mobilization in the field is due to microbial processes. In the areas of the transect downgradient of the ERD treatment area, however, the concentrations of OC, As, Fe and Mn in the groundwater are not elevated relative to background levels. The decrease in the dissolved concentration of OC can be attributed to mineralization by microorganisms. The losses of As, Fe and Mn from the dissolved phase must presumably be accompanied by their uptake onto aquifer solids, but chemical extractions provided evidence only for the enrichment of Fe(II). Nor could sorption of As(III) onto sediments be detected by X-ray absorption spectroscopy (XAS) against the background of native As in the sediments, which was present as As(V).

- by Azra Bilgin
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- Geochemistry, Arsenic, Groundwater Contamination, X ray absorption spectroscopy
- by Charley Yu
- •
- Environmental Science, Chemistry, Groundwater Contamination, Soil Mechanics

Machining and processing activities (and mining activities for U) produce particulate U and Pu, which can be transported in air as fine material, and physically in soil and water through various physical and biological transport processes. Dissolved U and Pu can be produced by chemical processing, leaching, or weathering of particulates, especially for U. Uranium is transported in groundwater primarily as dissolved U(VI). The dissolved species depends strongly upon the solution pH and dissolved carbonate concentration, as well as other aspects of water chemistry and substrate properties along the transport - pathways. In general, UO2 2+ dominates in waters less than pH 6, UO2OH + and (UO2)2CO3(OH)3 in waters in equilibrium with atmospheric CO2 between pH 6 and 7, and UO2(CO3)2 2- and UO2(CO3)3 4- in most waters above pH 7, and in carbonate-rich waters above pH 6. Pu chemistry is more complex. Depending upon redox and pH conditions, Pu is able to exist in 3 or 4 oxidation states in n...

- by James Conca
- •
- Groundwater Contamination, Water Chemistry, Surface Water, Humic acid

Water with high nitrate concentration (NO3 −) is unfit for human consumption, especially when its concentration exceeded the threshold limit (50 mg/l) recommended by the health authorities such as the World Health Organization (WHO). In Jordan, there is a great concern for determination and monitoring organic and inorganic pollutants that may reach groundwater. Nitrate is highly mobile and present in domestic, agricultural and industrial waste in Jordan, and thus this study focused initially on nitrate as both a contaminant of concern and as an indicator of potential groundwater contamination. The present study determined the extent of nitrate contamination in groundwater in the study area and examined the likely sources of NO3 −. A total of 248 groundwater samples were collected from 16 wells in different sites of Al-Hashimiya area, Zerqa Governorate, Jordan, and investigated for NO3 − concentrations. Moreover, measurements of temperature, electrical conductivity and pH were carried out in the field. Analysis was carried out according to the methods described by the American Public Health Association (APHA). Results showed that there was a dramatic increasing in NO3 − concentrations from the year 2001 to 2006 for some selected wells in the present study. NO3 − concentration in 2006 was ranged from 10 to 330 mg/l with an average of 77 mg/l. Overall, groundwater had elevated nitrate concentration with 92% of the samples containing more than 20 mg/l NO3 −, indicating the influence of human activities. This study has shown that there is a strong correlation between the nitrate concentration and the wastewater effluents as a source of pollution.

- by faisal athamneh
- •
- Geography, Groundwater, Housing, Groundwater Contamination

A polymer-surfactant flood was demonstrated for the recovery of coal tar at a former manufactured gas plant (MGP) site. The ground water was heated to reduce the viscosity of the coal tar and improve solubility. Polymer was used as a mobility control mechanism to reduce the affect of textural heterogeneities. In lab tests, the use of polymer significantly increased surfactant effectiveness. More than 80 % of the coal tar within the treatment zone was removed during the pilot study. Approximately 10 % of the recovered coal tar was solubilized and about 90 % of the coal tar was free-phase liquid indicating that mobilization was the predominant removal mechanism. INTRODUCTION A demonstration of micellar-polymer flooding has been completed at a former MGP site in Bloomington, Illinois. The objective was to use Surfactant Enhanced Aquifer Remediation (SEAR) to remove the free-phase coal tar from a shallow subsurface water-bearing unit. An innovation used during this surfactant flood was to use polymer for mobility control. Mobility control mechanisms reduce hydrodynamic instability caused by viscosity contrasts and reduce inefficiencies caused by aquifer heterogeneity. Mobility control was previously evaluated for surfactant-flooding at Hill Air Force Base, where injected foam was used to divert flow from high permeability zones to low-permeability zones (Szafranski et al. 1998). Hill Air Force Base is also the site for the first full-scale remediation project using SEAR (Londergan et al. 2001). The coal tar was present in the test area primarily as a dense non-aqueous phase liquid (DNAPL). Coal tar is a multi-component hydrocarbon, with a strong tendency to adhere to all surfaces. The design approach was to select a surfactant system capable of recovering the coal tar by solubilization and by mobilization. The objective was to remove all of the free-phase coal tar, leaving only residual DNAPL that would be trapped by capillary forces and would be incapable of flowing.

- by Varadarajan Dwarakanath and +1
- •
- Groundwater Contamination, Surfactant Flooding Agent
- by Stephen Worthington and +1
- •
- Groundwater Contamination, Multidisciplinary

This model is designed to provide an interpretation of the original layout of the former Sudbury Hall gasworks. The gasworks are a rare surviving example of an ornate private gasworks built in the style of the surrounding estate buildings. The Sudbury Estate being built in the restoration style, the gasworks was built in 1874 and was designed by George Devey, a noted architect of the time. The gasworks supplied the house and various properties in the village, operating up until the 1920’s.
The gasworks is Grade II listed and has been in urgent need of repair and the local community has formed the Sudbury Gasworks Restoration Trust (SGRT), a building preservation trust which aims to save the building and adapt it to serve the community once again (http://www.sudburygasworks.com/history/). Sudbury hall is located in the village of Sudbury, Derbyshire, UK and the nearby Hall is now a National Trust Property. This model is one of a series created by Russell Thomas for use in educational and public engagement projects.

- by Russell Thomas
- •
- History, Architecture, Industrial Archaeology, Groundwater Contamination

Many sites of groundwater contamination rely heavily on complex numerical models of flow and transport to develop closure plans. This has created a need for tools and approaches that can be used to build confidence in model predictions and make it apparent to regulators, policy makers, and the public that these models are sufficient for decision making. This confidence building is a long-term iterative process and it is this process that should be termed "model validation." Model validation is a process not an end result. That is, the process of model validation cannot always assure acceptable prediction or quality of the model. Rather, it provides safeguard against faulty models or inadequately developed and tested models. Therefore, development of a systematic approach for evaluating and validating subsurface predictive models and guiding field activities for data collection and long-term monitoring is strongly needed. This report presents a review of model validation studies that pertain to groundwater flow and transport modeling. Definitions, literature debates, previously proposed validation strategies, and conferences and symposia that focused on subsurface model validation are reviewed and discussed. The review is general in nature, but the focus of the discussion is on site-specific, predictive groundwater models that are used for making decisions regarding remediation activities and site closure. An attempt is made to compile most of the published studies on groundwater model validation and assemble what has been proposed or used for validating subsurface models. The aim is to provide a reasonable starting point to aid the development of the validation plan for the groundwater flow and transport model of the Faultless nuclear test conducted at the Central Nevada Test Area (CNTA).

- by Ahmed Hassan
- •
- Monte Carlo Simulation, Forecasting, Groundwater Contamination, Groundwater modeling

The study was conducted to investigate the iron (Fe) contamination in groundwater at Tangail municipality during the period from January to June 2011. Groundwater samples were collected from 18 locations, where 15 were tube-wells, 2 deep tubewells and 1 pump. The result of the study showed that the highest level of Fe (24.50 mg/l) was found at Dewla north, while the lowest level (1.03 mg/l) was recorded from Bepari para. The highest and lowest amount of Fe was found in ward 1 and 4,
respectively. The results were compared with the Bangladesh drinking water quality standards as well as with the international standards. In Bangladesh, permissible limit of Fe is 0.3-1.0 mg/l, whereas WHO standard level is 0.3 mg/l. All the samples were exceeded the standard levels of Fe, whereas ward 1, 2 and 7 were worstly affected. The study also reveal that the availability of Fe does not depend on the type of water sources, but it depends on the aquifers or water table. If the aquifer contains Fe, then the tube-well water will contain Fe or vice versa. These higher Fe concentrations found in the study area may be harmful for those families who are consuming the water from these sources on regular basis. Thus, to overcome this problem the consumers should not drink these higher amounts of Fe, and they should find other sources or replace the tube-well or treat the water before drinking and other domestic and household purposes.

- by Tanmoy Roy Tusher
- •
- Groundwater Contamination

Phosphogypsum (PG), the major waste material in phosphate fertilizer processing, has been known to contain enhanced levels of naturally-occurring radionuclides especially 226Ra.The lack of radioactivity data regarding Philippine phosphogypsum and its environmental behavior in the Philippine setting has brought concern on possible contamination of groundwater beneath the phosphogypsum ponds in Isabel, Leyte, Philippines. The radioactivity of Philippine phosphogypsum was determined and the leaching of 226Ra from phosphogypsum and through local soil was quantified. Level of 226Ra in groundwater samples in Isabel, Leyte, Philippines was also quantified to address the primary concern. It was found that the 226Ra activity in Philippine phosphogypsum is distributed in a wide range from 91.5 to 935 Bq/kg. As much as 5% of 226Ra can be leached from Philippine PG with deionized water. In vitro soil leach experiments suggest that the soil in the phosphate fertilizer plant area would be able to deter the intrusion of 226Ra into the water table. Compared to reported values of natural groundwater levels of 226Ra, the concentration of this radionuclide in Isabel, Leyte groundwater suggest that there is no 226Ra intrusion brought about by the presence of phosphogypsum ponds in the area.

- by Lorna Jean Palad
- •
- Water, Philippines, Groundwater Contamination, Multidisciplinary

Dissolved arsenic (As) in groundwater has reached concentrations
as high as 0.211 mg/L in the Kern Fan Element of the Kern Water
Bank, a proposed groundwater recharge project. General
constituent analyses and stable isotopes were utilized to identify
four distinct groundwater types: 1) a Sierra Nevada-sourced,
Na-HCOj water (eastside groundwater); 2) a Coast Rangesourced,
S04-rich water (westside groundwater); 3) an easternsourced
anthropogenically altered, mixed-ion water (anthro-east
groundwater); and 4) a western-sourced anthropogenically altered
Na-Cl water (anthro-west groundwater). Oil field and agricultural
activities such as brine disposal and pesticide application
account for anthropogenically altered waters.
The highest concentrations of dissolved As are closely associated
with the Na-HC03 water. Low As concentrations (<0.005 mg/L)
in Sierran recharge waters at the head of the flow path, combined
with minimal increases in total dissolved solids along the
groundwater flow path, suggest dissolution of aquifer framework
materials are the likely source of As in the main aquifer.
The western anthropogenically altered waters have slightly elevated
As concentrations and show evidence of possible alteration
by brine disposal, indicating human activities may be a potential
source of As. However, the western-altered waters are not
well connected hydraulically to the main aquifer; therefore human
activities appear to be relatively insignificant as a source of
dissolved As.

- by Geoffrey Thyne and +2
- •
- Groundwater Contamination, Groundwater Quality

Zona Citrícola is an important area for Mexico due to its citriculture activity. Situated in a sub-humid to humid climate adjacent to the Sierra Madre Oriental, this valley hosts an aquifer system that represents sequences of shales, marls, conglomerates, and alluvial deposits. Groundwater flows from mountainous recharge areas to the basin-fill deposits and provides base flows to supply drinking water to the adjacent metropolitan area of Monterrey. Recent studies examining the groundwater quality of the study area urge the mitigation of groundwater pollution. The objective of this study was to characterize the physical and chemical properties of the groundwater and to assess the processes controlling the groundwater's chemistry. Correlation was used to identify associations among various geochemical constituents. Factor analysis was applied to identify the water's chemical characteristics that were responsible for generating most of the variability within the dataset. Hierarchical cluster analysis was employed in combination with a post-hoc analysis of variance to partition the water samples into hydrochemical water groups: recharge waters (Ca-HCO3), transition zone waters (Ca-HCO3-SO4 to Ca-SO4-HCO3) and discharge waters (Ca-SO4). Inverse geochemical models of these groups were developed and constrained using PHREEQC to elucidate the chemical reactions controlling the water's chemistry between an initial (recharge) and final water. The primary reactions contributing to salinity were the following: (1) water-rock interactions, including the weathering of evaporitic rocks and dedolomitization; (2) dissolution of soil gas carbon dioxide; and (3) input from animal/human wastewater and manure in combination with by denitrification processes. Contributions from silicate weathering to salinity ranged from less important to insignificant. The findings suggest that it may not be cost-effective to regulate manure application to mitigate groundwater pollution.

- by Jürgen Mahlknecht
- •
- Hydrogeology, Hydrology, Groundwater, Groundwater Contamination

Background: 215 million gallons of water contaminated by radio-waste of phosphoric fertilizer (called “gypsum stack” or “phosphogypsum”) probably spilled into biggest Florida’s aquifer on August, 27th, but Mosaic society advised Authority only on September, 17th. In the last 20 years, this was the third incident for Mosaic.
Phosphogypsum is a waste by phosphoric fertilizer and it is radioactive due to the presence of naturally occurring uranium and thorium. It could also contain cadmium.
Methods: Scientific publications in the last 30 years and current evidences were collected. In the first part of review we analyzed history of nuclear Centrale del Garigliano (Italy). In the second part, a meta-analysis regarding Chernobyl incident has been performed, focused on the use of contaminated water. We use data only by Centrale del Garigliano and Chernobyl (and not other, such Fukushima) because in study we considered only spilling in not current water, that is used for agriculture and livestock. To study Floridian pollution, we compare Italian radioactivity/wide from nuclear/population density (and its effects on public health) with Floridian data, and we add to this cadmium toxicity.
Findings: Florida is known for sinkholes, but Florida is known also for fertilizer production: is possible combine natural and artificial hazards with people health safety and national security? Review analyzes agricultural/human use of undeclared contaminated water in the past (Chernobyl), and currently (Centrale del Garigliano) to predict which hazards for public health are more likely to occur in Florida.
Conclusions: all data confirm importance of communication to Authorities about chemical and nuclear incident (and biological, too) to restrict damage to health and save time for a more synergic effort between private and\or public agencies. Use of contaminated water is strictly correlated with increase of cardio-vascular disease, miscarriages/infant malformations and cancer due to DNA pathologies (duplications, deletions, etc).

- by Francesco Rosiello and +3
- •
- Groundwater Contamination, Contaminated Land, Groundwater Pollution, Water Pollution

Wastewater effluents from the textile and other dye-stuff industries contain significant amounts of synthetic dyes that require treatment to prevent groundwater contamination. In research aimed at biotechnology for treatment of azo dyes, this study examined 288 strains of azo-dye degrading bacteria to identify efficient strains and determine incubation times required for decolorization. Initial enrichment cultures were carried out using a mixture of four structurally different dyes (Acid Red 88, Reactive Black 5, Direct Red 81, and Disperse Orange 3) as the sole source of C and N to isolate the bacteria from soil, activated sludge, and natural asphalt. Six strains were selected for further study based on their prolific growth and ability to rapidly decolorize the dyes individually or in mixtures. Treatment times required by the most efficient strain, AS96 (Shewanella putrefaciens) were as short as 4 h for complete decolorization of 100 mg l−1 of AR-88 and DR-81 dyes under static conditions, and 6 and 8 h, respectively, for complete decolorization of RB-5 and DO-3. To our knowledge, these bacterial strains are the most efficient azo-dye degrading bacteria that have been described and may have practical application for biological treatment of dye-polluted wastewater streams.

- by muhammad arshad
- •
- Carbon, Groundwater Contamination, Activated Sludge, Applied microbiology

Várias atividades humanas são causadoras de problemas ambientais e a sociedade vem tentando combater isso. Os cemitérios são um exemplo de atividade que causa danos ao ambiente e põem em risco a saúde pública. Consequências como a poluição do solo e das águas superficiais e subterrâneas são encontrados em vários estudos realizados pelo Brasil. O presente trabalho fala sobre o potencial poluidor do Cemitério Municipal de Bandeirantes/PR.

- by Diego Da Silva and +1
- •
- Groundwater Contamination, Enviromental pollution

The city of Lagos is situated on a flat coastal dense forest of Nigeria with 2 broad distinct geological formations: The Abeokuta/Ilaro Formation and the quaternary formation of the coastal plain sands. Due to high rate of urbanization and intensive use of groundwater for domestic and industrial purposes, a large quantity of groundwater is being withdrawn from the coastal aquifer. Several dug wells and boreholes situated in the city area and outskirts (but mostly within residential areas) have been monitored for water level fluctuations and quality variations. Measured physical and chemical parameters as well as bacterial and coliform counts revealed groundwater contamination in many parts of the municipality. Comparison with similar studies in the last 15 – 20 years has shown a deteriorating groundwater quality that should generate concern and immediate remedial measures. The geology, drainage, chemistry and other related anthropo- genic factors play a major role in the spread of pollution in the area. Hence it is very important to determine the degree of vulnerability to pollution based on hydrogeological factors.

- by Segun Adelana
- •
- Hydrogeology, Water quality, Groundwater Contamination, Coastal Aquifer
- by Kristine Uhlman and +1
- •
- Groundwater Contamination, Groundwater Pollution, Groundwater Quality

12 The Maltese Islands are composed of two limestone aquifers, the Upper and Lower Coralline 13 Limestone separated by an aquitard, the 'Blue Clay'. The Lower Coralline Limestone is 14 overlain in part by the poorly permeable Globigerina Limestone. The upper perched aquifers 15 are discontinuous and have very limited saturated thickness and a short water level response 16 time to rainfall. Frequent detections of coliforms suggest a rapid route to groundwater. 17 However, the unsaturated zone has a considerable thickness in places and the primary 18 porosity of the Upper Coralline Limestone is high, so there is likely to be older recharge by 19 slow matrix flow as well as rapid recharge from fractures. Measurement of SF 6 from a 20 pumping station in a deep part of one of the perched aquifers indicated a mean saturated 21 zone age of about 15 years. The Main Sea Level aquifers (MSL) on both Malta and Gozo 22 have a large unsaturated thickness as water levels are close to sea level. On Malta, parts of 23 the aquifer are capped by the perched aquifers and more extensively by the Globigerina 24 Limestone. The limited detection of coliform bacteria suggests only some rapid recharge 25 from the surface via fractures or karst features. Transmissivity is low and tritium and 26 CFC/SF 6 data indicate that saturated zone travel times are in the range 15-40 years. On Gozo 27 the aquifer is similar but is more-extensively capped by impermeable Blue Clay. CFC data 28 show the saturated zone travel time is from 25 years to possibly more than 60 years. 29 Groundwater age is clearly related to the extent of low-permeability cover. The δ 13 C 30 signature of groundwater is related to the geochemical processes which occur along the 31 flowpath and is consistent with residence time ages in the sequence; perched aquifers<Malta 32 MSL<Gozo MSL. The 18 O and 2 H enriched isotopic signature of post 1983 desalinated 33 water can be seen in more-modern groundwater, particularly the urbanised areas of the 34 Applied Geochemistry. Groundwater residence time and movement in the Maltese islands -A geochemical approach 2 perched and Malta MSL aquifers. In all aquifers, movement of solutes from the surface 35 travelling slowly through the matrix provide a long term source of groundwater 36 contaminants such as nitrate. 37 sustainable yield of Cheju volcanic island, Korea. Environ. Geol. 33, 43-53.

- by Daren Gooddy
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- Geochemistry, Groundwater Contamination, Sea Level, Applied Geochemistry

The vulnerability of four European aquifers with different hydrogeological and climatic characteristics was evaluated using the COP method. The results obtained were statistically analyzed by determination coefficients to measure which factor has greater importance in the vulnerability index. Furthermore, a new parameter has been designed to measure the vulnerability for the whole of the aquifer. The results demonstrate that COP is a useful method to assess the vulnerability of the test sites under consideration. The results obtained are coherent with the conceptual model of each pilot aquifer and the available hydrogeological information (hydrographs, isotopic data, tracer tests). Fissured carbonate aquifers (diffuse flow systems) are less vulnerable than karst aquifers (conduit flow systems) and the vulnerability index is more positively correlated with the O factor (unsaturated zone protection capacity) in the first case. The karst aquifers are more vulnerable than fissured aquifers and they show a higher correlation between the C factor (karst features) and the vulnerability index. Climatic variation (precipitation for example) influences the final vulnerability index of the aquifers according to the weight in the index and the spatial distribution.

- by Natasa Ravbar
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- Water, Water resources, Statistical Analysis, Risk and Vulnerability

The Sierra Madre Oriental (SMO) is composed of ranges with important regional geological structures in highly fractured carbonate rocks (Abra Formation), which facilitate the recharge of aquifers. At the regional scale, recharge occurs in the western SMO and locally, in ranges such as Palmillas, La Colmena and Abra, while the regional discharge is to the east in the Huasteca zone. Intermountain valleys, such as El Salto, are located near the regional discharge zone. Three end members were identified in these regions, one related to local flow, another to intermediate and a third to regional flow. These flows define ternary mixing processes in groundwater. In this paper, the evolution of groundwater is studied, which is important for learning the system performance and hydrogeochemical processes through VISHMOD (Virtual Samples in Hydrochemical Modeling) methodology. The mixing model for the intermountain valleys indicates that many recharges occur, for which local flow contributes 68.3%, intermediate flow 12.3% and regional flow 19.4%. The inverse modeling shows that the water-rock interaction, precipitation and/or dissolution of calcite, gypsum and dolomite are the main processes occurring in the aquifer system of the intermountain valleys.

- by Jose Ramos and +3
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- Hydrogeology, Central America and Mexico, Groundwater, Groundwater Contamination

The assessment of groundwater vulnerability to pollution has proved to be an effective tool for the delineation of protection zones in areas affected by groundwater contamination due to intensive fertilizer applications. By modifying and optimizing the well known and widely used DRASTIC model it was possible to predict the intrinsic vulnerability to pollution as well as the groundwater pollution risk more accurately. This method incorporated the use of simple statistical and geostatistical techniques for the revision of the factor ratings and weightings of all the DRASTIC parameters under a GIS environment. The criterion for these modifications was the correlation coefficient of each parameter with the nitrates concentration in groundwater. On the basis of their statistical significance, some parameters were subtracted from the DRASTIC equation, while land use was considered as an additional DRASTIC parameter. Following the above-mentioned modifications, the correlation coefficient between groundwater pollution risk and nitrates concentration was considerably improved and rose to 33% higher than the original method. The model was applied to a part of Trifilia province, Greece, which is considered to be a typical Mediterranean region with readily available hydrogeological and hydrochemical data.

- by N. Lambrakis and +1
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- Engineering, Earth Sciences, Hydrogeology, Groundwater Contamination

Punjab is facing a crisis situation due to high levels of uranium, arsenic and selenium in underground water table of Punjab. Malwa belt of Punjab, namely, Ludhiana, Ferozepur, Roop Nagar and Fatehgarh sahib districts have high selenium contents in groundwater. Selenium Acceptable Limit (AL) for groundwater is fixed at 0.01 mg/l (ppm) by the Bureau of Indian Standards (BIS). In this report, groundwater quality data pertaining to selenium in the Malwa belt is reported. The highest value of selenium content of 0.14 mg/l (ppm) was reported in the water drawn from a handpump in the village Urna of Ludhiana district. Out of 80 villages of Ludhiana district with selenium content above AL value, 38 have selenium contamination levels higher than 0.015 mg/l (ppm). Roop Nagar, Ferozepur and Fatehgarh Sahib districts have 29, 9 and 17 villages with selenium content above the AL value, respectively. The possible health hazard effects of selenium are reported on the basis of studies carried out in the USA, China and Italy.

The coastal regions, particularly deltaic regions, are the most developed and most densely populated regions all over the world. These regions are facing many hydrological problems both due to natural conditions and man's activities. The problems due to natural conditions range from flooding due to cyclones and wave surge to drinking fresh water scarcity due to problem of sea water intrusion. Man's activities compound these problems further. Sea water intrusion is one of the severe problems faced by coastal regions. Natural conditions and man's activities both contribute to this problem. There exists an urgent need to study systematically the causes and remedial measures for sea water intrusion problem in coastal areas. This article presents the hydrological aspects, control measures and modelling of sea water intrusion in coastal aquifers.

- by C. P. Kumar
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- Groundwater, Groundwater Contamination, Groundwater modeling, Groundwater Hydrology

—The rising demand of energy in the Philippines paved way for the proliferation of different power sources, a more dependable energy source which is coal – based thermal power plant. The disposal of coal combustion products in ponds and landfills is a great concern because of its leachability. It can become a problem when elements from the ash are leached contaminating groundwater sources. The main goal of this research is to determine the concentration of heavy metals in the groundwater sources leached from coal combustion products and the to assess the physico-chemical parameters of water quality. Standard methods were employed in collection and determination of the pH, color, alkalinity, odor and temperature and the heavy metals; As, Cd, Cr, Cu, Pb, Mn, and Hg. Mn was found to have the highest concentration while Hg has the least concentration. The concentrations of heavy metals follow the trend Hg < Cd < Cu = Pb< Cr < As <Mn. Concentrations of heavy metals were detected but not excessive enough to be over the permissible limit set in the Philippine National Standards for Drinking Water thus making the groundwater potable with regards to the measured parameters in the study.