WorldWideScience

Sample records for determining seepage water

  1. Determining seepage water velocity by means of lysimeters; Bestimmung der Sickerwassergeschwindigkeit in Lysimetern

    Energy Technology Data Exchange (ETDEWEB)

    Klotz, D.; Seiler, K.P.

    1999-02-01

    The processes in the water-unsaturated zone have in the past received too little attention from hydrogeologists and their study by pedologists has been patchy. It is only recently that studies have been published, with for some part very diverse scientific approaches, which consider the water-unsaturated zone and the soil as a whole. There are small-scale and large-scale hydraulic approaches, hydraulic and first tracer-hydrological approaches. This poses the problem of how to transfer results obtained locally to larger spaces. Moreover, the homogeneity of substrates has been found to be such that hydraulic and tracer-hydrological approaches are unproblematic at the large scale, while at the small scale their results can only be interpreted with certain reservations. For example, this has led to findings of steady groundwater recharge at a large scale which contrast with findings at a smaller scale of a separation into highly variable matrix and bypass flows or into groundwater recharge and intermediate outflows. Studies at different levels of scale consequently bear different implications for material transport within and material export from specific landscape sections to underground or aboveground neighbouring compartments. The purpose of the present workshop on seepage water movement is to contribute to the establishment of facts on this issue, identify deficits, and stimulate future cooperation. [Deutsch] Die Prozesse in der wasserungesaettigten Zone wurden in der Vergangenheit zu wenig durch die Hydrogeologie und nur ausschnittsweise von der Pedologie betrachtet. Erst in neuerer Zeit mehren sich Arbeit, die die wasserungesaettigte Zone einschliesslich des Bodens integral betrachten, wobei die wissenschaftlichen Ansaetze z.T. sehr verschieden sind. Es gibt - klein- und grossskalige hydraulische Ansaetze, - hydraulische und erste tracerhydrologische Ansaetze und daraus erwaechst das Problem der Ueberleitung lokaler Ergebnisse auf groessere Raeume. Darueber

  2. A seepage meter designed for use in flowing water

    Science.gov (United States)

    Rosenberry, D.O.

    2008-01-01

    Seepage meters provide one of the most direct means to measure exchange of water across the sediment-water interface, but they generally have been unsuitable for use in fluvial settings. Although the seepage bag can be placed inside a rigid container to minimize velocity head concerns, the seepage cylinder installed in the sediment bed projects into and disrupts the flow field, altering both the local-scale fluid exchange as well as measurement of that exchange. A low-profile seepage meter designed for use in moving water was tested in a seepage meter flux tank where both current velocity and seepage velocity could be controlled. The conical seepage cylinder protrudes only slightly above the sediment bed and is connected via tubing to a seepage bag or flowmeter positioned inside a rigid shelter that is located nearby where current velocity is much slower. Laboratory and field tests indicate that the net effect of the small protrusion of the seepage cylinder into the surface water flow field is inconsequentially small for surface water currents up to 65 cm s-1. Current velocity affects the variability of seepage measurements; seepage standard deviation increased from ???2 to ???6 cm d-1 as current velocity increased from 9 to 65 cm s-1. Substantial bias can result if the shelter is not placed to minimize hydraulic gradient between the bag and the seepage cylinder.

  3. Multitracer studies for determining seepage water and anion movement in four types of soil using lysimeters with different functions and designs

    International Nuclear Information System (INIS)

    Knappe, S.; Russow, R.

    1999-01-01

    Lysimeter experiments based on the stable isotope tracer technique are a suitable means of examining the complex relationships governing water and material transport processes in the soil. The present paper reports on experiments in which water and nitrate movement was traced directly by means of lysimeters placed at different depths and using deuterium water and [ 15 N]N-nitrate for pulse marking. Extensive investigations carried out during the dissection of soil monoliths that had been used for many years in lysimeters offered an opportunity for stable isotope tracer studies aimed at determining seepage water and anion movement in undisturbed soils and, after dismantling the lysimeters, conducting soil analyses to find out more about the fate of nonpercolated tracers at various soil depths. Following other authors, bromide anions were additionally used as conservative tracers [de

  4. Development and evaluation of an ultrasonic ground water seepage meter.

    Science.gov (United States)

    Paulsen, R J; Smith, C F; O'Rourke, D; Wong, T F

    2001-01-01

    Submarine ground water discharge can influence significantly the near-shore transport and flux of chemicals into the oceans. Quantification of the sources and rates of such discharge requires a ground water seepage meter that provides continuous measurements at high resolution over an extended period of time. An ultrasonic flowmeter has been adapted for such measurements in the submarine environment. Connected to a steel collection funnel, the meter houses two piezoelectric transducers mounted at opposite ends of a cylindrical flow tube. By monitoring the perturbations of fluid flow on the propagation of sound waves inside the flow tube, the ultrasonic meter can measure both forward and reverse fluid flows in real time. Laboratory and field calibrations show that the ultrasonic meter can resolve ground water discharges on the order of 0.1 microm/sec, and it is sufficiently robust for deployment in the field for several days. Data from West Neck Bay, Shelter Island, New York, elucidate the temporal and spatial heterogeneity of submarine ground water discharge and its interplay with tidal loading. A negative correlation between the discharge and tidal elevation was generally observed. A methodology was also developed whereby data for the sound velocity as a function of temperature can be used to infer the salinity and source of the submarine discharge. Independent measurements of electrical conductance were performed to validate this methodology.

  5. Hurricane Impact on Seepage Water in Larga Cave, Puerto Rico

    Science.gov (United States)

    Vieten, Rolf; Warken, Sophie; Winter, Amos; Schröder-Ritzrau, Andrea; Scholz, Denis; Spötl, Christoph

    2018-03-01

    Hurricane-induced rainfall over Puerto Rico has characteristic δ18O values which are more negative than local rainfall events. Thus, hurricanes may be recorded in speleothems from Larga cave, Puerto Rico, as characteristic oxygen isotope excursions. Samples of 84 local rainfall events between 2012 and 2013 ranged from -6.2 to +0.3‰, whereas nine rainfall samples belonging to a rainband of hurricane Isaac (23-24 August 2012) ranged from -11.8 to -7.1‰. Cave monitoring covered the hurricane season of 2014 and investigated the impact of hurricane rainfall on drip water chemistry. δ18O values were measured in cumulative monthly rainwater samples above the cave. Inside the cave, δ18O values of instantaneous drip water samples were analyzed and drip rates were recorded at six drip sites. Most effective recharge appears to occur during the wet months (April-May and August-November). δ18O values of instantaneous drip water samples ranged from -3.5 to -2.4‰. In April 2014 and April 2015 some drip sites showed more negative δ18O values than the effective rainfall (-2.9‰), implying an influence of hurricane rainfall reaching the cave via stratified seepage flow months to years after the event. Speleothems from these drip sites in Larga cave have a high potential for paleotempestology studies.

  6. Multitracer studies for determining seepage water and anion movement in four types of soil using lysimeters with different functions and designs; Multitracer-Untersuchungen zur Bestimmung der Sickerwasser- und Anionenbewegung in vier Bodenformen bei Lysimetern unterschiedlicher Nutzung und Bauart

    Energy Technology Data Exchange (ETDEWEB)

    Knappe, S.; Russow, R. [UFZ - Umweltforschungszentrum Leipzig-Halle GmbH, Bad Lauchstaedt (Germany). Sektion Bodenforschung; Seeger, J. [Lysimeterstation Falkenberg (Germany)

    1999-02-01

    Lysimeter experiments based on the stable isotope tracer technique are a suitable means of examining the complex relationships governing water and material transport processes in the soil. The present paper reports on experiments in which water and nitrate movement was traced directly by means of lysimeters placed at different depths and using deuterium water and [{sup 15}N]N-nitrate for pulse marking. Extensive investigations carried out during the dissection of soil monoliths that had been used for many years in lysimeters offered an opportunity for stable isotope tracer studies aimed at determining seepage water and anion movement in undisturbed soils and, after dismantling the lysimeters, conducting soil analyses to find out more about the fate of nonpercolated tracers at various soil depths. Following other authors, bromide anions were additionally used as conservative tracers. [Deutsch] Zur Untersuchung der komplexen Zusammenhaenge des Wasser- und Stofftransportes im Boden bieten sich Lysimeterversuche unter Nutzung der stabilisotopen Tracertechnik an. In der vorliegenden Arbeit wird zunaechst ueber die direkte Verfolgung der Wasser- und Nitrat-Bewegung in tiefengestaffelten Lysimetern durch Pulsmarkierung mit Deuteriumwasser und [{sup 15}N]Nitrat berichtet. Im Rahmen von umfangreichen Untersuchungen bei der Zerlegung von langjaehrig in Lysimetern genutzten Bodenmonolithen bestand des weiteren die Moeglichkeit, stabilisotope Traceruntersuchungen zur Bestimmung der Sickerwasser- und Anionenbewegung an ungestoerten Boeden durchzufuehren und nach der Zerlegung der Lysimeter ueber entsprechende Analysen des Bodens Aussagen zum Verbleib der nicht perkolierten Tracer in verschiedenen Bodentiefen zu treffen. Zusaetzlich wurde dabei das von anderen Autoren bereits genutzte Bromid-Anion als sogenannter konservativer Tracer eingesetzt. (orig.)

  7. Using self-potential housing technique to model water seepage at the UNHAS housing Antang area

    Science.gov (United States)

    Syahruddin, Muhammad Hamzah

    2017-01-01

    The earth's surface has an electric potential that is known as self-potentiall (SP). One of the causes of the electrical potential at the earth's surface is water seepage into the ground. Electrical potential caused by water velocity seepage into the ground known as streaming potential. How to model water seepage into the ground at the housing Unhas Antang? This study was conducted to answer these questions. The self-potential measurements performed using a simple digital voltmeter Sanwa brand PC500 with a precision of 0.01 mV. While the coordinates of measurements points are self-potential using Global Positioning System. Mmeasurements results thus obtained are plotted using surfer image distribution self-potential housing Unhas Antang. The self-potential data housing Unhas Antang processed by Forward Modeling methods to get a model of water infiltration into the soil. Housing Unhas Antang self-potential has a value of 5 to 23 mV. Self-potential measurements carried out in the rainy season so it can be assumed that the measurement results caused by the velocity water seepage into the ground. The results of modeling the velocity water seepage from the surface to a depth of 3 meters was 2.4 cm/s to 0.2 cm /s. Modeling results showed that the velocity water seepage of the smaller with depth.

  8. Seepage determinations through auxiliary dike in Chingaza reservoir using radioactive tracers

    International Nuclear Information System (INIS)

    Sanches, L.; Obando, E.; Jimenez, G.; Torrez, E.

    1986-01-01

    Isotope techniques used in hydrology and developed during the last ten years in Colombia are usually tracer techniques based on the use of nuclides either introduced or naturally present in water. A problem of current content importance in hydraulics structures is seepage and the problems connected with it, such as impermeability of dams docks and their foundations. Many approaches are used to investigate these questions, but the simplest and most successful is the radiometric method. Radiometric observation of the flow of water through the earth dock involves introducing at a fixed point in the flow of water a radioactive solution and then following its movement downstream of the dock, and finding the place where it goes using appropriate detectors arranged at fixed control points. This paper describes the mean of choosing the injection points, the techniques for introducing radioactive solution and the conditions that must be borne in mind when selecting the radioisotope and determining its optimum activity. (author)

  9. Seepage from uranium tailing ponds and its impact on ground water

    International Nuclear Information System (INIS)

    Rahn, P.H.; Mabes, D.L.

    1978-01-01

    A typical uranium mill produces about 1800 metric tons of tailing per day. An assessment of the seepage from an unlined tailing impoundment of a hypothetical mill in northwestern New Mexico indicates that about 2x10 5 m 3 /yr of water will seep over a period of 23 years. The seepage water will move vertically to the water table, and then spread out radially and ultimately downgradient with ground water. The principal dissolved contaminants in the tailing pond liquid are radium, thorium, sulfate, iron, manganese, and selenium; in addition, the liquid is acidic (pH=2). Many contaminants precipitate out as neutralization of seepage water occurs. At the termination of mill operation, radium will have advanced about 0.4 m and thorium no more than 0.1 m below the bottom of the tailing pond

  10. Pond-aquifer flow and water availability in the vicinity of two coastal area seepage ponds, Glynn and Bulloch Counties, Georgia

    Science.gov (United States)

    Clarke, John S.; Rumman, Malek Abu

    2005-01-01

    Pond-aquifer flow and water availability at excavated seepage pond sites in Glynn County and in southern Bulloch County, Georgia, were evaluated to determine their potential as sources of water supply for irrigation. Excavated seepage ponds derive water primarily from ground water seeping into the pond, in a manner similar to a dug well completed in a surficial aquifer. The availability of water from seepage ponds is controlled by the permeability of surficial deposits, the amount of precipitation recharging the ground-water system, and the volume of water stored in the pond. The viability of seepage ponds as supplies for irrigation is limited by low seepage rates and high dependence on climatic conditions. Ponds will not refill unless there is adequate precipitation to recharge the surficial aquifer, which subsequently drains (seeps) into the pond. Ground-water seepage was estimated using a water-budget approach that utilized on-site climatic and hydrologic measurements, computing pond-volume changes during pond pumping tests, and by digital simulation using steady-state and transient ground-water flow models. From August 1999 to May 2000, the Glynn County pond was mostly losing water (as indicated by negative net seepage); whereas from October 2000 to June 2001, the Bulloch County pond was mostly gaining water. At both sites, most ground-water seepage entered the pond following major rainfall events that provided recharge to the surficial aquifer. Net ground-water seepage, estimated using water-budget analysis and simulation, ranged from -11.5 to 15 gallons per minute (gal/min) at the Glynn County pond site and from -55 to 31 gal/min at the Bulloch County pond site. Simulated values during pumping tests indicate that groundwater seepage to both ponds increases with decreased pond stage. At the Glynn County pond, simulated net ground-water seepage varied between 7.8 gal/min at the beginning of the test (high pond stage and low hydraulic gradient) and 103 gal

  11. Quantification of Seepage in Groundwater Dependent Wetlands

    DEFF Research Database (Denmark)

    Johansen, Ole; Beven, Keith; Jensen, Jacob Birk

    2018-01-01

    Restoration and management of groundwater dependent wetlands require tools for quantifying the groundwater seepage process. A method for determining point estimates of the groundwater seepage based on water level observations is tested. The study is based on field data from a Danish rich fen...

  12. Study on of Seepage Flow Velocity in Sand Layer Profile as Affected by Water Depth and Slope Gradience

    Science.gov (United States)

    Han, Z.; Chen, X.

    2017-12-01

    BACKGROUND: The subsurface water flow velocity is of great significance in understanding the hydrodynamic characteristics of soil seepage and the influence of interaction between seepage flow and surface runoff on the soil erosion and sediment transport process. OBJECTIVE: To propose a visualized method and equipment for determining the seepage flow velocity and measuring the actual flow velocity and Darcy velocity as well as the relationship between them.METHOD: A transparent organic glass tank is used as the test soil tank, the white river sand is used as the seepage test material and the fluorescent dye is used as the indicator for tracing water flow, so as to determine the thickness and velocity of water flow in a visualized way. Water is supplied at the same flow rate (0.84 L h-1) to the three parts with an interval of 1m at the bottom of the soil tank and the pore water velocity and the thickness of each water layer are determined under four gradient conditions. The Darcy velocity of each layer is calculated according to the water supply flow and the discharge section area. The effective discharge flow pore is estimated according to the moisture content and porosity and then the relationship between Darcy velocity and the measured velocity is calculated based on the water supply flow and the water layer thickness, and finally the correctness of the calculation results is verified. RESULTS: According to the velocity calculation results, Darcy velocity increases significantly with the increase of gradient; in the sand layer profile, the flow velocity of pore water at different depths increases with the increase of gradient; under the condition of the same gradient, the lower sand layer has the maximum flow velocity of pore water. The air-filled porosity of sand layer determines the proportional relationship between Darcy velocity and pore flow velocity. CONCLUSIONS: The actual flow velocity and Darcy velocity can be measured by a visualized method and the

  13. Evaluation of the conditions imposed by the fracture surface geometry on water seepage through fractured porous media

    International Nuclear Information System (INIS)

    Fuentes, Nestor O.; Faybishenko, B.

    2003-01-01

    In order to determine the geometric patterns of the fracture surfaces that imposes conditions on the fluid flow through fractured porous media, a series a fracture models have been analyzed using the RIMAPS technique and the variogram method. Results confirm that the main paths followed by the fluid channels are determined by the surface topography and remain constant during water seepage evolution. Characteristics scale lengths of both situations: fracture surface and the flow of water, are also found. There exists a relationship between the scale lengths corresponding to each situation. (author)

  14. Uncertainty of the Soil–Water Characteristic Curve and Its Effects on Slope Seepage and Stability Analysis under Conditions of Rainfall Using the Markov Chain Monte Carlo Method

    Directory of Open Access Journals (Sweden)

    Weiping Liu

    2017-10-01

    Full Text Available It is important to determine the soil–water characteristic curve (SWCC for analyzing slope seepage and stability under the conditions of rainfall. However, SWCCs exhibit high uncertainty because of complex influencing factors, which has not been previously considered in slope seepage and stability analysis under conditions of rainfall. This study aimed to evaluate the uncertainty of the SWCC and its effects on the seepage and stability analysis of an unsaturated soil slope under conditions of rainfall. The SWCC model parameters were treated as random variables. An uncertainty evaluation of the parameters was conducted based on the Bayesian approach and the Markov chain Monte Carlo (MCMC method. Observed data from granite residual soil were used to test the uncertainty of the SWCC. Then, different confidence intervals for the model parameters of the SWCC were constructed. The slope seepage and stability analysis under conditions of rainfall with the SWCC of different confidence intervals was investigated using finite element software (SEEP/W and SLOPE/W. The results demonstrated that SWCC uncertainty had significant effects on slope seepage and stability. In general, the larger the percentile value, the greater the reduction of negative pore-water pressure in the soil layer and the lower the safety factor of the slope. Uncertainties in the model parameters of the SWCC can lead to obvious errors in predicted pore-water pressure profiles and the estimated safety factor of the slope under conditions of rainfall.

  15. Characterization of Coal Micro-Pore Structure and Simulation on the Seepage Rules of Low-Pressure Water Based on CT Scanning Data

    Directory of Open Access Journals (Sweden)

    Gang Zhou

    2016-07-01

    Full Text Available This paper used the X-ray three-dimensional (3D microscope and acquired, through CT scanning, the 3D data of the long-frame coal sample from the Daliuta Coal Mine. Then, the 3D datacube reconstructed from the coal’s CT scanning data was visualized with the use of Avizo, an advanced visualization software (FEI, Hillsboro, OR, USA. By means of a gray-scale segmentation technique, the model of the coal’s micro-pore structure was extracted from the object region, and the precise characterization was then conducted. Finally, the numerical simulation on the water seepage characteristics in the coal micro-pores model under the pressure of 3 MPa was performed on the CFX platform. Results show that the seepage of low-pressure water exhibited preference to the channels with large pore radii, short paths, and short distance from the outlet. The seepage pressure of low-pressure water decreased gradually along the seepage direction, while the seepage velocity of low-pressure water decreased gradually along the direction from the pore center to the wall. Regarding the single-channel seepage behaviors, the seepage velocity and mass flow rate of water seepage in the X direction were the largest, followed by the values of the seepage in the Y direction, and the seepage velocity and mass flow rate of water seepage in the Z direction were the smallest. Compared with the results in single-channel seepage, the dual-channel seepage in the direction of (X + Y and the multi-channel seepage in the direction of (X + Y + Z exhibited significant increases in the overall seepage velocity. The present study extends the application of 3D CT scanning data and provides a new idea and approach for exploring the seepage rules in coal micro-pore structures.

  16. Determining the REV for Fracture Rock Mass Based on Seepage Theory

    Directory of Open Access Journals (Sweden)

    Lili Zhang

    2017-01-01

    Full Text Available Seepage problems of the fractured rock mass have always been a heated topic within hydrogeology and engineering geology. The equivalent porous medium model method is the main method in the study of the seepage of the fractured rock mass and its engineering application. The key to the method is to determine a representative elementary volume (REV. The FractureToKarst software, that is, discrete element software, is a main analysis tool in this paper and developed by a number of authors. According to the standard of rock classification established by ISRM, this paper aims to discuss the existence and the size of REV of fractured rock masses with medium tractility and provide a general method to determine the existence of REV. It can be gleaned from the study that the existence condition of fractured rock mass with medium tractility features average fracture spacing smaller than 0.6 m. If average fracture spacing is larger than 0.6 m, there is no existence of REV. The rationality of the model is verified by a case study. The present research provides a method for the simulation of seepage field in fissured rocks.

  17. ABSTRACTION OF DRIFT SEEPAGE

    International Nuclear Information System (INIS)

    Wilson, Michael L.

    2001-01-01

    Drift seepage refers to flow of liquid water into repository emplacement drifts, where it can potentially contribute to degradation of the engineered systems and release and transport of radionuclides within the drifts. Because of these important effects, seepage into emplacement drifts is listed as a ''principal factor for the postclosure safety case'' in the screening criteria for grading of data in Attachment 1 of AP-3.15Q, Rev. 2, ''Managing Technical Product Inputs''. Abstraction refers to distillation of the essential components of a process model into a form suitable for use in total-system performance assessment (TSPA). Thus, the purpose of this analysis/model is to put the information generated by the seepage process modeling in a form appropriate for use in the TSPA for the Site Recommendation. This report also supports the Unsaturated-Zone Flow and Transport Process Model Report. The scope of the work is discussed below. This analysis/model is governed by the ''Technical Work Plan for Unsaturated Zone Flow and Transport Process Model Report'' (CRWMS MandO 2000a). Details of this activity are in Addendum A of the technical work plan. The original Work Direction and Planning Document is included as Attachment 7 of Addendum A. Note that the Work Direction and Planning Document contains tasks identified for both Performance Assessment Operations (PAO) and Natural Environment Program Operations (NEPO). Only the PAO tasks are documented here. The planning for the NEPO activities is now in Addendum D of the same technical work plan and the work is documented in a separate report (CRWMS MandO 2000b). The Project has been reorganized since the document was written. The responsible organizations in the new structure are the Performance Assessment Department and the Unsaturated Zone Department, respectively. The work plan for the seepage abstraction calls for determining an appropriate abstraction methodology, determining uncertainties in seepage, and providing

  18. Evaluating origins and water seepage rates at the subdam A of the Dong Mo reservoir using environmental isotope technique

    International Nuclear Information System (INIS)

    Bui Dac Dung; Trinh Van Giap; Dang Anh Minh; Nguyen Van Hoan

    2008-01-01

    Environmental isotope techniques have been world-widely used for investigating origins and the rates of the seepage - leakage water at reservoir dams. We have conducted a research on the use of environmental isotope techniques for evaluating the origin of the seepage water and the seepage rate at the sub dam A of the Dong Mo reservoir. The main works were collecting water samples, analyzing for 18 O/ 16 O, 2 H(D)/ 1 H ratios, analyzing for 3 H(T) and chemical contents. Findings of the project showed that: a) Waters at the piezometers on the top and the 1st roof are not originated from lake water; b) Waters at the piezometers on 1st and 2nd levels, as well as seepage waters at the dam toe are mixed of lake and ground waters, and the old river bed could be the channel for ground water upcoming from beneath the dam body; c) The transit times of water from the lake to the observation points are from 3 to 4 months, and the seepage velocity is of about 1.1x10 -3 cm/s; d) The findings from tritium analyses show that all waters around the Dong Mo area are recent waters recharged regularly by meteoric water. (author)

  19. Temporal variability of exchange between groundwater and surface water based on high-frequency direct measurements of seepage at the sediment-water interface

    Science.gov (United States)

    Rosenberry, Donald O.; Sheibley, Rich W.; Cox, Stephen E.; Simonds, Frederic W.; Naftz, David L.

    2013-01-01

    Seepage at the sediment-water interface in several lakes, a large river, and an estuary exhibits substantial temporal variability when measured with temporal resolution of 1 min or less. Already substantial seepage rates changed by 7% and 16% in response to relatively small rain events at two lakes in the northeastern USA, but did not change in response to two larger rain events at a lake in Minnesota. However, seepage at that same Minnesota lake changed by 10% each day in response to withdrawals from evapotranspiration. Seepage increased by more than an order of magnitude when a seiche occurred in the Great Salt Lake, Utah. Near the head of a fjord in Puget Sound, Washington, seepage in the intertidal zone varied greatly from −115 to +217 cm d−1 in response to advancing and retreating tides when the time-averaged seepage was upward at +43 cm d−1. At all locations, seepage variability increased by one to several orders of magnitude in response to wind and associated waves. Net seepage remained unchanged by wind unless wind also induced a lake seiche. These examples from sites distributed across a broad geographic region indicate that temporal variability in seepage in response to common hydrological events is much larger than previously realized. At most locations, seepage responded within minutes to changes in surface-water stage and within minutes to hours to groundwater recharge associated with rainfall. Likely implications of this dynamism include effects on water residence time, geochemical transformations, and ecological conditions at and near the sediment-water interface.

  20. Abating coal tar seepage into surface water bodies using sheet piles with sealed interlocks

    International Nuclear Information System (INIS)

    Collingwood, B.I.; Boscardin, M.D.; Murdock, R.F.

    1995-01-01

    A former coal tar processing facility processed crude coal tar supplied from manufactured gas plants in the area. Coal-tar-contaminated ground water from the site was observed seeping through an existing timber bulkhead along a tidal river and producing a multicolored sheen on the surface of the river. As part of a short-term measure to abate the seepage into the river, 64-m long anchored sheet pile wall with sheet pile wing walls at each end was constructed inland of the of the timber bulkhead. The sheet piles extended to low-permeability soils at depth and the interlocks of the sheet piles were provided with polyurethane rubber seals. Based on postconstruction observations for leakage and sheens related to leakage, the steel sheet piles with polyurethane rubber interlock seals appeared to provide a successful seal and abate coal-tar-contaminated ground water seepage into the river. The tie rod penetration sealing proved to be a more problematic detail, but through several postconstruction grouting episodes, an effective seal was produced

  1. Application of carbon isotopes to detect seepage out of coalbed natural gas produced water impoundments

    International Nuclear Information System (INIS)

    Sharma, Shikha; Baggett, Joshua K.

    2011-01-01

    Highlights: → Coalbed natural gas extraction results in large amount of produced water. → Risk of deterioration of ambient water quality. → Carbon isotope natural tracer for detecting seepage from produced water impoundments. - Abstract: Coalbed natural gas (CBNG) production from coal bed aquifers requires large volumes of produced water to be pumped from the subsurface. The produced water ranges from high quality that meets state and federal drinking water standards to low quality due to increased salinity and/or sodicity. The Powder River Basin of northeastern Wyoming is a major coalbed natural gas producing region, where water quality generally decreases moving from the southeastern portion of the basin towards the center. Most produced water in Wyoming is disposed into impoundments and other surface drainages, where it may infiltrate into shallow groundwater. Groundwater degradation caused by infiltration of CBNG produced water holding impoundments into arid, soluble salt-rich soils is an issue of immense importance because groundwater is a major source for stock water, irrigation, and drinking water for many small communities in these areas. This study examines the potential of using stable C isotope signatures of dissolved inorganic C (δ 13 C DIC ) to track the fate of CBNG produced water after it is discharged into the impoundments. Other geochemical proxies like the major cations and major anions were used in conjunction with field water quality measurements to understand the geochemical differences between CBNG produced waters and ambient waters in the study area. Samples were collected from the CBNG discharge outfalls, produced water holding impoundments, and monitoring wells from different parts of the Powder River Basin and analyzed for δ 13 C DIC . The CBNG produced waters from outfalls and impoundments have positive δ 13 C DIC values that fall within the range of +12 per mille to +22 per mille, distinct from the ambient regional surface and

  2. Toxicity of Water Samples Collected in the Vicinity of F and H Seepage Basin 1990-1995

    Energy Technology Data Exchange (ETDEWEB)

    Specht, W.L. [Westinghouse Savannah River Company, AIKEN, SC (United States); Bowers, B.

    1996-09-01

    Water and contaminants from the F- and H-Area Seepage Basins outcrop as shallow groundwater seeps down gradient from the basins. In 1990, 1991, 1993, 1994, and 1995, toxicity tests were performed on water collected from a number of these seeps, as well as from several locations in Fourmile Branch and several uncontaminated reference locations.

  3. Abstraction of Drift Seepage

    International Nuclear Information System (INIS)

    J.T. Birkholzer

    2004-01-01

    This model report documents the abstraction of drift seepage, conducted to provide seepage-relevant parameters and their probability distributions for use in Total System Performance Assessment for License Application (TSPA-LA). Drift seepage refers to the flow of liquid water into waste emplacement drifts. Water that seeps into drifts may contact waste packages and potentially mobilize radionuclides, and may result in advective transport of radionuclides through breached waste packages [''Risk Information to Support Prioritization of Performance Assessment Models'' (BSC 2003 [DIRS 168796], Section 3.3.2)]. The unsaturated rock layers overlying and hosting the repository form a natural barrier that reduces the amount of water entering emplacement drifts by natural subsurface processes. For example, drift seepage is limited by the capillary barrier forming at the drift crown, which decreases or even eliminates water flow from the unsaturated fractured rock into the drift. During the first few hundred years after waste emplacement, when above-boiling rock temperatures will develop as a result of heat generated by the decay of the radioactive waste, vaporization of percolation water is an additional factor limiting seepage. Estimating the effectiveness of these natural barrier capabilities and predicting the amount of seepage into drifts is an important aspect of assessing the performance of the repository. The TSPA-LA therefore includes a seepage component that calculates the amount of seepage into drifts [''Total System Performance Assessment (TSPA) Model/Analysis for the License Application'' (BSC 2004 [DIRS 168504], Section 6.3.3.1)]. The TSPA-LA calculation is performed with a probabilistic approach that accounts for the spatial and temporal variability and inherent uncertainty of seepage-relevant properties and processes. Results are used for subsequent TSPA-LA components that may handle, for example, waste package corrosion or radionuclide transport

  4. Tracing the source of emerging seepage water at failure slope downstream, Kampung Bharu Bukit Tinggi, Bentong, Pahang

    International Nuclear Information System (INIS)

    Lakam Mejus; Wan Zakaria Wan Mohd Tahir; Md Shahid Ayub; Jeremy Andy; Johari Latif

    2006-01-01

    This paper discusses method and monitoring result of the source of seepage water emerging (mud flow) at downstream toe of the failure slope at Kampung Bharu Bukit Tinggi, Bentong Pahang. In this investigation, a saline-tracer experiment was conducted by injecting its solution into a drain at an upstream section (old road to Janda Baik town) where a pipeline was found leaking in the vicinity of the roadside and flowing towards hill slopes. Some parts of flowing water was left undetected and seeped through the soil on its way to downstream area. Seepage water downstream was monitored by using a conductivity sensor hooked up to a CR10X data logger and optical back scattering conductivity probes. From the result, it is believed that the source of seepage water is related to the water from the leaking pipeline upstream. The travelling time for the leaking water to reach downstream slope failure was within 16-17 hours. Based on this preliminary investigation, one can conclude that seepage water is one of the main contributing factors that cause slope failure in the vicinity of the investigated hill slopes. Further investigation to understand the failure mechanism at this place by conducting multi-experimental approaches in different seasons, particularly during continuous rain storms. (Author)

  5. Surface Water Transport for the F/H Area Seepage Basins Groundwater Program

    International Nuclear Information System (INIS)

    Chen, Kuo-Fu.

    1995-01-01

    The contribution of the F- and H-Area Seepage Basins (FHSBs) tritium releases to the tritium concentration in the Savannah River are presented in this report. WASP5 was used to simulate surface water transport for tritium releases from the FHSBs. The WASP5 model was qualified with the 1993 tritium measurements at US Highway 301. The tritium concentrations in Fourmile Branch and the Savannah River were calculated for tritium releases from FHSBs. The calculated tritium concentrations above normal environmental background in the Savannah River, resulting from FHSBs releases, drop from 1.25 pCi/ml (<10% of EPA Drinking Water Guide) in 1995 to 0.0056 pCi/ml in 2045

  6. Geochemical characterisation of seepage and drainage water quality from two sulphide mine tailings impoundments: Acid mine drainage versus neutral mine drainage

    Science.gov (United States)

    Heikkinen, P.M.; Raisanen, M.L.; Johnson, R.H.

    2009-01-01

    Seepage water and drainage water geochemistry (pH, EC, O2, redox, alkalinity, dissolved cations and trace metals, major anions, total element concentrations) were studied at two active sulphide mine tailings impoundments in Finland (the Hitura Ni mine and Luikonlahti Cu mine/talc processing plant). The data were used to assess the factors influencing tailings seepage quality and to identify constraints for water treatment. Changes in seepage water quality after equilibration with atmospheric conditions were evaluated based on geochemical modelling. At Luikonlahti, annual and seasonal changes were also studied. Seepage quality was largely influenced by the tailings mineralogy, and the serpentine-rich, low sulphide Hitura tailings produced neutral mine drainage with high Ni. In contrast, drainage from the high sulphide, multi-metal tailings of Luikonlahti represented typical acid mine drainage with elevated contents of Zn, Ni, Cu, and Co. Other factors affecting the seepage quality included weathering of the tailings along the seepage flow path, process water input, local hydrological settings, and structural changes in the tailings impoundment. Geochemical modelling showed that pH increased and some heavy metals were adsorbed to Fe precipitates after net alkaline waters equilibrated with the atmosphere. In the net acidic waters, pH decreased and no adsorption occurred. A combination of aerobic and anaerobic treatments is proposed for Hitura seepages to decrease the sulphate and metal loading. For Luikonlahti, prolonged monitoring of the seepage quality is suggested instead of treatment, since the water quality is still adjusting to recent modifications to the tailings impoundment.

  7. Variations on seepage water geochemistry induced by natural and anthropogenic microclimatic changes: Implications for the speleothems growth conditions

    Science.gov (United States)

    Fernandez-Cortes, A.; Sanchez-Moral, S.; Canaveras, J. C.; Cuevas, J.; Cuezva, S.; Andreu, J. M.; Abella, R.

    2009-04-01

    During an annual cycle the effect of microclimatic changes (natural and anthropogenic origin) on the geochemical characteristics of seepage water and mineral precipitation rates was analyzed, for two karstic caves under opposing environmental stability and energy exchange with exterior. On the one hand Castañar cave (Caceres, Spain), an extremely controlled show cave with limited visitation showing a minimum exchange rate of energy with the outer atmosphere and, secondly, Canelobre cave (Alicante, Spain), a widely visited cave where the anthropogenic impact generates both high-speed and high-energy environmental changes. Microclimatic variations play a key role in CO2-dessgasing caused by the imbalance of pCO2 between the karstic water and the cave air, favoring the slow processes of mineral precipitation. Thus, a pCO2-range of seepage water have been detected for each cave (from 10-2.30/-2.35 to 10-2.47/-2.52 bar for Castañar cave, and from 10-2.8/-2.85 to 10-2.95/-3.0 bar for Canelobre cave) where the mineral oversaturation prevails, determining the type and rate of mineral precipitation in each cave. Finally, it analyzes how the changes on the oversaturation/ precipitation states are controlled by microclimatic variations, such as: 1) natural underground air renewal through the porous system of upper soil and the network of host-rock fissures (isolating membranes), or else through the cave entrance, 2) cumulative disruptions in the pCO2 levels of cave air due to the presence of visitors, and 3) forced ventilation of the subterranean atmosphere due to the uncontrolled opening of cave entrances. The obtained results reinforce the significance of the microclimatic fluctuations on short time scales in the dynamic and evolution of the subterranean karst system, in terms of rates of mineral precipitation and growth of speleothems. Likewise the interpretations are useful in order to ensure the constant climate required for the conservation of caves.

  8. Model evaluation of seepage from uranium tailings disposal above and below the water table

    International Nuclear Information System (INIS)

    Nelson, R.W.; Meyer, P.R.; Oberlander, P.L.; Sneider, S.C.; Mayer, D.W.; Reisenauer, A.E.

    1983-03-01

    Model simulations identify the rate and amount of leachate released to the environment if disposed uranium mill tailings come into contact with ground water or if seepage from tailings reaches ground water. In this study, simulations of disposal above and below the water table, with various methods of leachate control, were compared. Three leachate control methods were used in the comparisons: clay bottom liners; stub-sidewall clay liners; and tailings drains with sumps, with the effluent pumped back from the sumps. The best leachate control for both above and below the water table is a combination of the three methods. The combined methods intercept up to 80% of the leachate volume in pits above the water table and intercept essentially all of the leachate in pits below the water table. Effluent pumping, however, requires continuous energy costs and an alternative method of disposal for the leachate that cannot be reused as makeup water in the mill process. Without the drains or effluent pumping, the clay bottom liners have little advantage in terms of the total volume of leachate lost. The clay liners do reduce the rate of leachate flow to the ground water, but the flow continues for a longer time. The buffering, sorption, and chemical reactions of the leachate passing directly through the liner are also advantages of the liner

  9. Mechanical model of water inrush from coal seam floor based on triaxial seepage experiments

    Institute of Scientific and Technical Information of China (English)

    Yihui Pang; Guofa Wang; Ziwei Ding

    2014-01-01

    In order to study the mechanism of confined water inrush from coal seam floor, the main influences on permeability in the process of triaxial seepage experiments were analyzed with methods such as laboratory experiments, theoretical analysis and mechanical model calculation. The crack extension rule and the ultimate destruction form of the rock specimens were obtained. The mechanism of water inrush was explained reasonably from mechanical point of view. The practical criterion of water inrush was put forward. The results show that the rock permeability ‘‘mutation’’ phe-nomenon reflects the differences of stress state and cracks extension rate when the rock internal crack begins to extend in large-scale. The rock ultimate destruction form is related to the rock lithology and the angle between crack and principal stress. The necessary condition of floor water inrush is that the mining pressure leads to the extension and transfixion of the crack. The sufficient condition of floor water inrush is that the confined water’s expansionary stress in normal direction and shear stress in tangential direction must be larger than the internal stress in the crack. With the two conditions satisfied at the same time, the floor water inrush accident will occur.

  10. Calibration and application of an automated seepage meter for monitoring water flow across the sediment-water interface.

    Science.gov (United States)

    Zhu, Tengyi; Fu, Dafang; Jenkinson, Byron; Jafvert, Chad T

    2015-04-01

    The advective flow of sediment pore water is an important parameter for understanding natural geochemical processes within lake, river, wetland, and marine sediments and also for properly designing permeable remedial sediment caps placed over contaminated sediments. Automated heat pulse seepage meters can be used to measure the vertical component of sediment pore water flow (i.e., vertical Darcy velocity); however, little information on meter calibration as a function of ambient water temperature exists in the literature. As a result, a method with associated equations for calibrating a heat pulse seepage meter as a function of ambient water temperature is fully described in this paper. Results of meter calibration over the temperature range 7.5 to 21.2 °C indicate that errors in accuracy are significant if proper temperature-dependence calibration is not performed. The proposed calibration method allows for temperature corrections to be made automatically in the field at any ambient water temperature. The significance of these corrections is discussed.

  11. Long Term Effects of Acid Irrigation at the Hoeglwald on Seepage Water Chemistry and Nutrient Cycling

    International Nuclear Information System (INIS)

    Weis, Wendelin; Baier, Roland; Huber, Christian; Goettlein, Axel

    2007-01-01

    In order to test the hypothesis of aluminium toxicity induced by acid deposition, an experimental acid irrigation was carried out in a mature Norway spruce stand in Southern Germany (Hoeglwald). The experiment comprised three plots: no irrigation, irrigation (170 mm a -1 ), and acid irrigation with diluted sulphuric acid (pH of 2.6-2.8). During the seven years of acid irrigation (1984-1990) water containing 0.43 mol c m -2 a -1 of protons and sulphate was added with a mean pH of 3.2 (throughfall + acid irrigation water) compared to 4.9 (throughfall) on both control plots. Most of the additional proton input was consumed in the organic layer and the upper mineral soil. Acid irrigation resulted in a long lasting elevation of sulphate concentrations in the seepage water. Together with sulphate both aluminium and appreciable amounts of base cations were leached from the main rooting zone. The ratio between base cations (Ca + Mg + K) and aluminium was 0.79 during acid irrigation and 0.92 on the control. Neither tree growth and nutrition nor the pool of exchangeable cations were affected significantly. We conclude that at this site protection mechanisms against aluminium toxicity exist and that additional base cation runoff can still be compensated without further reduction of the supply of exchangeable base cations in the upper mineral soil

  12. Seepage into PEP tunnel

    International Nuclear Information System (INIS)

    Weidner, H.

    1990-01-01

    The current rate of seepage into the PEP tunnel in the vicinity of IR-10 is very low compared to previous years. Adequate means of handling this low flow are in place. It is not clear whether the reduction in the flow is temporary, perhaps due to three consecutive dry years, or permanent due to drainage of a perched water table. During PEP construction a large amount of effort was expended in attempts to seal the tunnel, with no immediate effect. The efforts to ''manage'' the water flow are deemed to be successful. By covering equipment to protect it from dripping water and channeling seepage into the drainage gutters, the seepage has been reduced to a tolerable nuisance. There is no sure, safe procedure for sealing a leaky shotcreted tunnel

  13. Leakage and Seepage of CO2 from Geologic Carbon Sequestration Sites: CO2 Migration into Surface Water

    International Nuclear Information System (INIS)

    Oldenburg, Curt M.; Lewicki, Jennifer L.

    2005-01-01

    Geologic carbon sequestration is the capture of anthropogenic carbon dioxide (CO 2 ) and its storage in deep geologic formations. One of the concerns of geologic carbon sequestration is that injected CO 2 may leak out of the intended storage formation, migrate to the near-surface environment, and seep out of the ground or into surface water. In this research, we investigate the process of CO 2 leakage and seepage into saturated sediments and overlying surface water bodies such as rivers, lakes, wetlands, and continental shelf marine environments. Natural CO 2 and CH 4 fluxes are well studied and provide insight into the expected transport mechanisms and fate of seepage fluxes of similar magnitude. Also, natural CO 2 and CH 4 fluxes are pervasive in surface water environments at levels that may mask low-level carbon sequestration leakage and seepage. Extreme examples are the well known volcanic lakes in Cameroon where lake water supersaturated with respect to CO 2 overturned and degassed with lethal effects. Standard bubble formation and hydrostatics are applicable to CO 2 bubbles in surface water. Bubble-rise velocity in surface water is a function of bubble size and reaches a maximum of approximately 30 cm s -1 at a bubble radius of 0.7 mm. Bubble rise in saturated porous media below surface water is affected by surface tension and buoyancy forces, along with the solid matrix pore structure. For medium and fine grain sizes, surface tension forces dominate and gas transport tends to occur as channel flow rather than bubble flow. For coarse porous media such as gravels and coarse sand, buoyancy dominates and the maximum bubble rise velocity is predicted to be approximately 18 cm s -1 . Liquid CO 2 bubbles rise slower in water than gaseous CO 2 bubbles due to the smaller density contrast. A comparison of ebullition (i.e., bubble formation) and resulting bubble flow versus dispersive gas transport for CO 2 and CH 4 at three different seepage rates reveals that

  14. Application of environmental isotopes and hydrochemistry in the identification of source of seepage and likely connection with lake water in Lesser Himalaya, Uttarakhand, India

    Science.gov (United States)

    Rai, Shive Prakash; Singh, Dharmaveer; Rai, Ashwani Kumar; Kumar, Bhishm

    2017-12-01

    Oxygen (δ^{18}O) and hydrogen (δ2H and 3H) isotopes of water, along with their hydrochemistry, were used to identify the source of a newly emerged seepage water in the downstream of Lake Nainital, located in the Lesser Himalayan region of Uttarakhand, India. A total of 57 samples of water from 19 different sites, in and around the seepage site, were collected. Samples were analysed for chemical tracers like Ca^{++}, Mg^{++}, Na+, K+, {SO4}^{-} and Cl- using an Ion Chromatograph (Dionex IC-5000). A Dual Inlet Isotope Ratio Mass Spectrometer (DIIRMS) and an Ultra-Low Level Liquid Scintillation Counter (ULLSC), were used in measurements of stable isotopes (δ2H and δ^{18}O) and a radioisotope (3H), respectively. Results obtained in this study repudiate the possibility of any likely connection between seepage water and the lake water, and indicate that the source of seepage water is mainly due to locally recharged groundwater. The study suggests that environmental isotopes (δ2H, δ^{18}O and 3H) can effectively be used as `tracers' in the detection of the source of seepage water in conjunction with other hydrochemical tracers, and can help in water resource management and planning.

  15. Application of the neutron gamma method to a study of water seepage under a rice plantation

    International Nuclear Information System (INIS)

    Puard, M.; Couchat, P.; Moutonnet, P.

    1980-01-01

    In order to determine the share of percolation in the pollution by pesticides (particularly Lindane) being carried down in the drainage water of rice plantations, an application of the neutron gamma method under rice cultivation in the Camargue is suggested. A preliminary laboratory study enabled a comparison to be made between deuteriated water (DHO) and tritiated water (THO) used as water tracers in the determination of the dispersive phenomena and retention in a column of saturated soil [fr

  16. Evaluation of ground-water flow and hydrologic budget for Lake Five-O, a seepage lake in northwestern Florida

    Science.gov (United States)

    Grubbs, J.W.

    1995-01-01

    Temporal and spatial distributions of ground-water inflow to, and leakage from Lake Five-O, a softwater, seepage lake in northwestern Florida, were evaluated using hydrologic data and simulation models of the shallow ground-water system adjacent to the lake. The simulation models indicate that ground-water inflow to the lake and leakage from the lake to the ground-water system are the dominant components in the total inflow (precipitation plus ground-water inflow) and total outflow (evaporation plus leakage) budgets of Lake Five-O. Simlulated ground-water inflow and leakage were approximately 4 and 5 times larger than precipitation inputs and evaporative losses, respectively, during calendar years 1989-90. Exchanges of water between Lake Five-O and the ground-water system were consistently larger than atmospheric-lake exchanges. A consistent pattern of shallow ground-water inflow and deep leakage was also evident throughout the study period. The mean time of travel from ground-water that discharges at Lake Five-O (time from recharge at the water table to discharge at the lake) was estimated to be within a range of 3 to 6 years. Flow-path evaluations indicated that the intermediate confining unit probably has a negligible influence on the geochemistry of ground-water inflow to Lake Five-O. The hydrologic budgets and flow-path evaluations provide critical information for developing geochemical budgets for Lake Five-O and for improving the understanding of the relative importance of various processes that regulate the acid-neutralizing capacity of softwater seepage lakes in Florida.

  17. Characterization of Preferential Ground-Water Seepage From a Chlorinated Hydrocarbon-Contaminated Aquifer to West Branch Canal Creek, Aberdeen Proving Ground, Maryland, 2002-04

    Science.gov (United States)

    Majcher, Emily H.; Phelan, Daniel J.; Lorah, Michelle M.; McGinty, Angela L.

    2007-01-01

    , relatively low concentrations of chlorinated daughter compounds, and insignificant concentrations of methane in shallow pore water samples. These seeps were primarily along the creek edge or formed a dendritic-like pattern between the wetland and creek channel. In contrast, seep locations characterized as diffuse seeps contained relatively high concentrations of chlorinated daughter compounds (or a mixture of daughter and parent compounds) and detectable methane concentrations in shallow pore water samples. These seeps were primarily along the wetland boundary. Qualitative thermal infrared surveys coupled with quantitative verification of temperature differences, and screening for volatile organic compound and methane concentrations proved to be effective tools in determining the overall extent of preferential seepage. Hydrologic and physical properties of wetland sediments were characterized at two focused and one diffuse seep location. In the seeps with focused discharge, measured seepage was consistent over the tidal cycle, whereas more variability with tidal fluctuation was measured in the diffuse seep location. At all locations, areas were identified within the general seep boundaries where discharge was minimal. In all cases, the geometric mean of non-zero vertical flux measurements was greater than those previously reported in the non-seep wetland sediments using flow-net analysis. Flux was greater in the focused discharge areas than in the diffuse discharge area, and all fluxes were within the range reported in the literature for wetland discharge. Vertical hydraulic conductivity estimated from seepage flux and a mean vertical gradient at seeps with focused discharge resulted in a minimum hydraulic conductivity two orders of magnitude greater than those estimated in the non-seep sediment. In contrast, vertical conductivity estimates at a diffuse seep were similar to estimates along a nearby line of section through a non-seep area. Horizontal hydraulic cond

  18. SEEPAGE/INVERT INTERACTIONS

    International Nuclear Information System (INIS)

    P.S. Domski

    2000-01-01

    As directed by a written development plan (CRWMS M andO 1999a), a conceptual model for water entering the drift and reacting with the invert materials is to be developed. The purpose of this conceptual model is to assist Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department in modeling the geochemical environment within a repository drift, thus allowing PAO to provide a more detailed and complete in-drift geochemical model abstraction, and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near-Field Environment (NFE), Revision 2 (NRC 1999). This AMR also seeks to: (1) Develop a logical conceptual model for physical/chemical interactions between seepage and the invert materials; (2) screen potential processes and reactions that may occur between seepage and invert to evaluate the potential consequences of the interactions; and (3) outline how seepage/invert processes may be quantified. This document provides the conceptual framework for screening out insignificant processes and for identifying and evaluating those seepage/invert interactions that have the potential to be important to subsequent PAO analyses including the Engineered Barrier System (EBS) physical and chemical model abstraction effort. This model has been developed to serve as a basis for the in-drift geochemical analyses performed by PAO. Additionally, the concepts discussed within this report may also apply to certain near and far-field geochemical processes and may have conceptual application within the unsaturated zone (UZ) and saturated zone (SZ) transport modeling efforts. The seepage/invert interactions will not directly affect any principal factors

  19. Simulation of water seepage through a vadose zone in fractured rock

    International Nuclear Information System (INIS)

    Fuentes, Nestor O.

    2003-01-01

    In order to improve our understanding of the vadose zone in fractured rock, obtaining useful tools to simulate, predict and prevent subsurface contamination, a three-dimensional model has been developed from the base of recent two-dimensional codes. Fracture systems are simulated by means of a dynamical evolution of a random-fuse network model, and the multiphase expression of Richards equation is used to describe fluid displacements. Physical situations presented here emphasized the importance of fracture connectivity and spatial variability on the seepage evolution through the vadose zone, and confirm the existence of dendritic patterns along localized preferential paths. (author)

  20. Investigation of water seepage through porous media using X-ray imaging technique

    Science.gov (United States)

    Jung, Sung Yong; Lim, Seungmin; Lee, Sang Joon

    2012-07-01

    SummaryDynamic movement of wetting front and variation of water contents through three different porous media were investigated using X-ray radiography. Water and natural sand particles were used as liquid and porous media in this study. To minimize the effects of minor X-ray attenuation and uneven illumination, the flat field correction (FFC) was applied before determining the position of wetting front. In addition, the thickness-averaged (in the direction of the X-ray penetration) water content was obtained by employing the Beer-Lambert law. The initial inertia of water droplet influences more strongly on the vertical migration, compared to the horizontal migration. The effect of initial inertia on the horizontal migration is enhanced as sand size decreases. The pattern of water transport is observed to be significantly affected by the initial water contents. As the initial water contents increases, the bulb-type transport pattern is shifted to a trapezoidal shape. With increasing surface temperature, water droplets are easily broken on the sand surface. This consequently decreases the length of the initial inertia region. Different from the wetting front migration, the water contents at the initial stage clearly exhibit a preferential flow along the vertical direction. The water transport becomes nearly uniform in all directions beyond the saturation state.

  1. Regeneration of Mature Norway Spruce Stands: Early Effects of Selective Cutting and Clear Cutting on Seepage Water Quality and Soil Fertility

    Directory of Open Access Journals (Sweden)

    Wendelin Weis

    2001-01-01

    Full Text Available The cutting of trees influences element turnover in the forest ecosystem. The reduction of plant uptake, as well as an increased mineralization and nitrification due to higher soil temperature and soil moisture, can lead to considerable losses of nutrients from the main rooting zone. This may result in a reduced soil fertility and a decrease in drinking water quality due to high nitrate concentrations in the seepage water. In Bavaria (Germany selective cutting is preferred to clear cutting when initiating the regeneration of Norway spruce stands with European beech. This paper summarizes the early effects of both forest management practices on soil fertility and seepage water quality for three different sites. Shown are the concentrations of nitrogen and base cations in the seepage water as well as the water and ion fluxes during the first year after tree cut. Nutrient inputs decreased on thinned plots and even more at clear-cuts. Nitrate concentrations in the seepage water are hardly affected by moderate thinning; however, on clear-cuts, the nitrate concentration increases significantly, and base cations are lost from the upper mineral soil. This effect is less obvious at sites where a dense ground vegetation, which is able to take up excess nitrogen, exists.

  2. Drift-Scale THC Seepage Model

    Energy Technology Data Exchange (ETDEWEB)

    C.R. Bryan

    2005-02-17

    The purpose of this report (REV04) is to document the thermal-hydrologic-chemical (THC) seepage model, which simulates the composition of waters that could potentially seep into emplacement drifts, and the composition of the gas phase. The THC seepage model is processed and abstracted for use in the total system performance assessment (TSPA) for the license application (LA). This report has been developed in accordance with ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Post-Processing Analysis for THC Seepage) Report Integration'' (BSC 2005 [DIRS 172761]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this report. The plan for validation of the models documented in this report is given in Section 2.2.2, ''Model Validation for the DS THC Seepage Model,'' of the TWP. The TWP (Section 3.2.2) identifies Acceptance Criteria 1 to 4 for ''Quantity and Chemistry of Water Contacting Engineered Barriers and Waste Forms'' (NRC 2003 [DIRS 163274]) as being applicable to this report; however, in variance to the TWP, Acceptance Criterion 5 has also been determined to be applicable, and is addressed, along with the other Acceptance Criteria, in Section 4.2 of this report. Also, three FEPS not listed in the TWP (2.2.10.01.0A, 2.2.10.06.0A, and 2.2.11.02.0A) are partially addressed in this report, and have been added to the list of excluded FEPS in Table 6.1-2. This report has been developed in accordance with LP-SIII.10Q-BSC, ''Models''. This report documents the THC seepage model and a derivative used for validation, the Drift Scale Test (DST) THC submodel. The THC seepage model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral

  3. Drift-Scale THC Seepage Model

    International Nuclear Information System (INIS)

    C.R. Bryan

    2005-01-01

    The purpose of this report (REV04) is to document the thermal-hydrologic-chemical (THC) seepage model, which simulates the composition of waters that could potentially seep into emplacement drifts, and the composition of the gas phase. The THC seepage model is processed and abstracted for use in the total system performance assessment (TSPA) for the license application (LA). This report has been developed in accordance with ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Post-Processing Analysis for THC Seepage) Report Integration'' (BSC 2005 [DIRS 172761]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this report. The plan for validation of the models documented in this report is given in Section 2.2.2, ''Model Validation for the DS THC Seepage Model,'' of the TWP. The TWP (Section 3.2.2) identifies Acceptance Criteria 1 to 4 for ''Quantity and Chemistry of Water Contacting Engineered Barriers and Waste Forms'' (NRC 2003 [DIRS 163274]) as being applicable to this report; however, in variance to the TWP, Acceptance Criterion 5 has also been determined to be applicable, and is addressed, along with the other Acceptance Criteria, in Section 4.2 of this report. Also, three FEPS not listed in the TWP (2.2.10.01.0A, 2.2.10.06.0A, and 2.2.11.02.0A) are partially addressed in this report, and have been added to the list of excluded FEPS in Table 6.1-2. This report has been developed in accordance with LP-SIII.10Q-BSC, ''Models''. This report documents the THC seepage model and a derivative used for validation, the Drift Scale Test (DST) THC submodel. The THC seepage model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral alteration on flow in rocks surrounding drifts. The DST THC submodel uses a drift

  4. Analysis of the Harmfulness of Water-Inrush from Coal Seam Floor Based on Seepage Instability Theory

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A theory of seepage instability was used to estimate the harmfulness of water-inrush from a coal seam floor in a particular coal mine of the Mining Group, Xuzhou.Based on the stratum column chart in this coal mine, the distribution of stress in mining floors when the long-wall mining was respectively pushed along to 100 m and to 150 m was simulated by using the numerical software (RFPA2D).The permeability parameters of the coal seam floor are described given the relationship between permeability parameters.Strain and the water-inrush-indices were calculated.The water-inrush-index was 67.2% when the working face was pushed to 100 m, showing that water-inrush is possible and it was 1630% when the working face was pushed to 150 m, showing that water-inrush is quite probable.The results show that as long-wall mining is pushed along, the failure zone is enlarged, the strain increased, and fissures developed correspondingly, resulting in the formation of water-inrush channels.Accompanied by the failure of the strata, the permeability increased exponentially.In contrast, the non-Darcy flow β factor and the acceleration coefficient decreased exponentially, while the increase in the water-inrush-index was nearly exponential and the harmfulness of water-inrush in the coal mine increased accordingly.

  5. Hydrogeologic setting, water budget, and preliminary analysis of ground-water exchange at Lake Starr, a seepage lake in Polk County, Florida

    Science.gov (United States)

    Swancar, Amy; Lee, T.M.; O'Hare, T. M.

    2000-01-01

    Lake Starr, a 134-acre seepage lake of multiple-sinkhole origin on the Lake Wales Ridge of central Florida, was the subject of a detailed water-budget study from August 1996 through July 1998. The study monitored the effects of hydrogeologic setting, climate, and ground-water pumping on the water budget and lake stage. The hydrogeologic setting of the Lake Starr basin differs markedly on the two sides of the lake. Ground water from the surficial aquifer system flows into the lake from the northwest side of the basin, and lake water leaks out to the surficial aquifer system on the southeast side of the basin. Lake Starr and the surrounding surficial aquifer system recharge the underlying Upper Floridan aquifer. The rate of recharge to the Upper Floridan aquifer is determined by the integrity of the intermediate confining unit and by the downward head gradient between the two aquifers. On the inflow side of the lake, the intermediate confining unit is more continuous, allowing ground water from the surficial aquifer system to flow laterally into the lake. Beneath the lake and on the southeast side of the basin, breaches in the intermediate confining unit enhance downward flow to the Upper Floridan aquifer, so that water flows both downward and laterally away from the lake through the ground-water flow system in these areas. An accurate water budget, including evaporation measured by the energy-budget method, was used to calculate net ground-water flow to the lake, and to do a preliminary analysis of the relation of net ground-water fluxes to other variables. Water budgets constructed over different timeframes provided insight on processes that affect ground-water interactions with Lake Starr. Weekly estimates of net ground-water flow provided evidence for the occurrence of transient inflows from the nearshore basin, as well as the short-term effects of head in the Upper Floridan aquifer on ground-water exchange with the lake. Monthly water budgets showed the effects

  6. Non-Darcy Flow Experiments of Water Seepage through Rough-Walled Rock Fractures

    Directory of Open Access Journals (Sweden)

    Xiao-dong Ni

    2018-01-01

    Full Text Available The knowledge of flow phenomena in fractured rocks is very important for groundwater-resources management in hydrogeological engineering. The most commonly used tool to approximate the non-Darcy behavior of the flow velocity is the well-known Forchheimer equation, deploying the “inertial” coefficient β that can be estimated experimentally. Unfortunately, the factor of roughness is imperfectly considered in the literature. In order to do this, we designed and manufactured a seepage apparatus that can provide different roughness and aperture in the test; the rough fracture surface is established combining JRC and 3D printing technology. A series of hydraulic tests covering various flows were performed. Experimental data suggest that Forchheimer coefficients are to some extent affected by roughness and aperture. At last, favorable semiempirical Forchheimer equation which can consider fracture aperture and roughness was firstly derived. It is believed that such studies will be quite useful in identifying the limits of applicability of the well-known “cubic law,” in further improving theoretical/numerical models associated with fluid flow through a rough fracture.

  7. A GIS-based, confined aquifer, hypothetical model of ground-water seepage into a former mining open pit

    International Nuclear Information System (INIS)

    Salama, A; Negeed, E.R.

    2010-01-01

    Groundwater seepage into a former mining site in Egypt is proposed for simulation. This site was used for basalt extraction. After the mining activities had stopped a large open pit was left over and groundwater seeped into the pit forming a lake. The pit has a dimension of approximately 1200 x 600 x 30 m. Because of the lack of field data, several scenarios may be hypothesized to explain the filling of these open pits with water. In this paper, one of these scenarios is studied. It is suggested that this water comes from an underneath confined aquifer. Through fractures in the host rock, water seeped upwards into the open pit. To estimate the rate at which water seeps into the lake, numerical study based on the finite element method is performed. Firstly, geo-referencing of the site was performed using GIS. The boundary of the lake was then digitized and elevation contours was defined. These data was then imported into grid-builder software to generate a two-dimensional triangular mesh which was then used by hydro-geosphere software to build the three-dimensional mesh and solve the problem. It was found that the set of discrete fractures was insufficient to fill the lake in the time span that was actually elapsed to fill up the lake which is on the order of two to three years.

  8. Seepage Calibration Model and Seepage Testing Data

    International Nuclear Information System (INIS)

    Dixon, P.

    2004-01-01

    The purpose of this Model Report is to document the Seepage Calibration Model (SCM). The SCM is developed (1) to establish the conceptual basis for the Seepage Model for Performance Assessment (SMPA), and (2) to derive seepage-relevant, model-related parameters and their distributions for use in the SMPA and seepage abstraction in support of the Total System Performance Assessment for License Application (TSPA-LA). The SCM is intended to be used only within this Model Report for the estimation of seepage-relevant parameters through calibration of the model against seepage-rate data from liquid-release tests performed in several niches along the Exploratory Studies Facility (ESF) Main Drift and in the Cross Drift. The SCM does not predict seepage into waste emplacement drifts under thermal or ambient conditions. Seepage predictions for waste emplacement drifts under ambient conditions will be performed with the SMPA (see upcoming REV 02 of CRWMS M and O 2000 [153314]), which inherits the conceptual basis and model-related parameters from the SCM. Seepage during the thermal period is examined separately in the Thermal Hydrologic (TH) Seepage Model (see BSC 2003 [161530]). The scope of this work is (1) to evaluate seepage rates measured during liquid-release experiments performed in several niches in the Exploratory Studies Facility (ESF) and in the Cross Drift, which was excavated for enhanced characterization of the repository block (ECRB); (2) to evaluate air-permeability data measured in boreholes above the niches and the Cross Drift to obtain the permeability structure for the seepage model; (3) to use inverse modeling to calibrate the SCM and to estimate seepage-relevant, model-related parameters on the drift scale; (4) to estimate the epistemic uncertainty of the derived parameters, based on the goodness-of-fit to the observed data and the sensitivity of calculated seepage with respect to the parameters of interest; (5) to characterize the aleatory uncertainty

  9. Investigation of Seepage Meter Measurements in Steady Flow and Wave Conditions.

    Science.gov (United States)

    Russoniello, Christopher J; Michael, Holly A

    2015-01-01

    Water exchange between surface water and groundwater can modulate or generate ecologically important fluxes of solutes across the sediment-water interface. Seepage meters can directly measure fluid flux, but mechanical resistance and surface water dynamics may lead to inaccurate measurements. Tank experiments were conducted to determine effects of mechanical resistance on measurement efficiency and occurrence of directional asymmetry that could lead to erroneous net flux measurements. Seepage meter efficiency was high (average of 93%) and consistent for inflow and outflow under steady flow conditions. Wave effects on seepage meter measurements were investigated in a wave flume. Seepage meter net flux measurements averaged 0.08 cm/h-greater than the expected net-zero flux, but significantly less than theoretical wave-driven unidirectional discharge or recharge. Calculations of unidirectional flux from pressure measurements (Darcy flux) and theory matched well for a ratio of wave length to water depth less than 5, but not when this ratio was greater. Both were higher than seepage meter measurements of unidirectional flux made with one-way valves. Discharge averaged 23% greater than recharge in both seepage meter measurements and Darcy calculations of unidirectional flux. Removal of the collection bag reduced this net discharge. The presence of a seepage meter reduced the amplitude of pressure signals at the bed and resulted in a nearly uniform pressure distribution beneath the seepage meter. These results show that seepage meters may provide accurate measurements of both discharge and recharge under steady flow conditions and illustrate the potential measurement errors associated with dynamic wave environments. © 2014, National Ground Water Association.

  10. Changes in contaminant composition at landfill sites. (9). ; Application of soil covering to treatment of alkaline seepage water. Umetate ni okeru odaku seibun no doko. (9). ; Alkali sei shinsutsueki no gaido shori

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Y; Sugai, T; Masuda, T; Watanabe, Y; Kobayashi, S [Saitama Institute of Environmental Pollution, Saitama (Japan)

    1990-10-29

    Recently, alkaline seepage water has been found in many landfill sites. Strong alkaline seepage water results from the use of alkaline agents, such as quicklime and slaked lime, for water removal from waste. In the present report, the neutralizing ability of different types of soil is studied to provide a method to neutralize seepage water by using soil covering at landfill sites. Results show that clay contained in soil is playing a major role in neutralizing alkaline seepage penetrating the soil. Clay generally has negative electric charges, suggesting that positive ions in alkaline water is neutralized after being replaced by hydrogen ions. Another major factor is the carbonate ion and carbon dioxide existing in soil, which precipitate and solidify calcium hydroxide as calcium carbonate to achieve neutralization. Investigations indicate that top soil comprising volcanic ash is useful as material for soil covering. 2 figs., 5 tabs.

  11. SEEPAGE/BACKFILL INTERACTIONS

    International Nuclear Information System (INIS)

    Mariner, P.

    2000-01-01

    As directed by written development plan (CRWMS M andO 1999a), a sub-model of seepage/backfill interactions is developed and presented in this document to support the Engineered Barrier System (EBS) Physical and Chemical Environment Model. The purpose of this analysis is to assist Performance Assessment Operations (PAO) and the Engineered Barrier Performance Department in modeling the geochemical environment within a repository drift. In this analysis, a conceptual model is developed to provide PAO a more detailed and complete in-drift geochemical model abstraction and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near Field Environment (NFE) Revision 2 (NRC 1999). The development plan calls for a sub-model that evaluates the effect on water chemistry of chemical reactions between water that enters the drift and backfill materials in the drift. The development plan specifically requests an evaluation of the following important chemical reaction processes: dissolution-precipitation, aqueous complexation, and oxidation-reduction. The development plan also requests the evaluation of the effects of varying seepage and drainage fluxes, varying temperature, and varying evaporation and condensation fluxes. Many of these effects are evaluated in a separate Analysis/Model Report (AMR), ''Precipitates Salts Analysis AMR'' (CRWMS M andO 2000), so the results of that AMR are referenced throughout this AMR

  12. SEEPAGE/BACKFILL INTERACTIONS

    Energy Technology Data Exchange (ETDEWEB)

    P. Mariner

    2000-04-14

    As directed by written development plan (CRWMS M&O 1999a), a sub-model of seepage/backfill interactions is developed and presented in this document to support the Engineered Barrier System (EBS) Physical and Chemical Environment Model. The purpose of this analysis is to assist Performance Assessment Operations (PAO) and the Engineered Barrier Performance Department in modeling the geochemical environment within a repository drift. In this analysis, a conceptual model is developed to provide PAO a more detailed and complete in-drift geochemical model abstraction and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near Field Environment (NFE) Revision 2 (NRC 1999). The development plan calls for a sub-model that evaluates the effect on water chemistry of chemical reactions between water that enters the drift and backfill materials in the drift. The development plan specifically requests an evaluation of the following important chemical reaction processes: dissolution-precipitation, aqueous complexation, and oxidation-reduction. The development plan also requests the evaluation of the effects of varying seepage and drainage fluxes, varying temperature, and varying evaporation and condensation fluxes. Many of these effects are evaluated in a separate Analysis/Model Report (AMR), ''Precipitates Salts Analysis AMR'' (CRWMS M&O 2000), so the results of that AMR are referenced throughout this AMR.

  13. R Reactor seepage basins soil moisture and resistivity field investigation using cone penetrometer technology, Savannah River Site, Aiken, South Carolina

    International Nuclear Information System (INIS)

    Harris, M.K.

    2000-01-01

    The focus of this report is the summer 1999 investigation of the shallow groundwater system using cone penetrometer technology characterization methods to determine if the water table is perched beneath the R Reactor Seepage Basins (RRSBs)

  14. Seepage Calibration Model and Seepage Testing Data

    Energy Technology Data Exchange (ETDEWEB)

    S. Finsterle

    2004-09-02

    The purpose of this Model Report is to document the Seepage Calibration Model (SCM). The SCM was developed (1) to establish the conceptual basis for the Seepage Model for Performance Assessment (SMPA), and (2) to derive seepage-relevant, model-related parameters and their distributions for use in the SMPA and seepage abstraction in support of the Total System Performance Assessment for License Application (TSPA-LA). This Model Report has been revised in response to a comprehensive, regulatory-focused evaluation performed by the Regulatory Integration Team [''Technical Work Plan for: Regulatory Integration Evaluation of Analysis and Model Reports Supporting the TSPA-LA'' (BSC 2004 [DIRS 169653])]. The SCM is intended to be used only within this Model Report for the estimation of seepage-relevant parameters through calibration of the model against seepage-rate data from liquid-release tests performed in several niches along the Exploratory Studies Facility (ESF) Main Drift and in the Cross-Drift. The SCM does not predict seepage into waste emplacement drifts under thermal or ambient conditions. Seepage predictions for waste emplacement drifts under ambient conditions will be performed with the SMPA [''Seepage Model for PA Including Drift Collapse'' (BSC 2004 [DIRS 167652])], which inherits the conceptual basis and model-related parameters from the SCM. Seepage during the thermal period is examined separately in the Thermal Hydrologic (TH) Seepage Model [see ''Drift-Scale Coupled Processes (DST and TH Seepage) Models'' (BSC 2004 [DIRS 170338])]. The scope of this work is (1) to evaluate seepage rates measured during liquid-release experiments performed in several niches in the Exploratory Studies Facility (ESF) and in the Cross-Drift, which was excavated for enhanced characterization of the repository block (ECRB); (2) to evaluate air-permeability data measured in boreholes above the niches and the Cross

  15. Seepage Calibration Model and Seepage Testing Data

    International Nuclear Information System (INIS)

    Finsterle, S.

    2004-01-01

    The purpose of this Model Report is to document the Seepage Calibration Model (SCM). The SCM was developed (1) to establish the conceptual basis for the Seepage Model for Performance Assessment (SMPA), and (2) to derive seepage-relevant, model-related parameters and their distributions for use in the SMPA and seepage abstraction in support of the Total System Performance Assessment for License Application (TSPA-LA). This Model Report has been revised in response to a comprehensive, regulatory-focused evaluation performed by the Regulatory Integration Team [''Technical Work Plan for: Regulatory Integration Evaluation of Analysis and Model Reports Supporting the TSPA-LA'' (BSC 2004 [DIRS 169653])]. The SCM is intended to be used only within this Model Report for the estimation of seepage-relevant parameters through calibration of the model against seepage-rate data from liquid-release tests performed in several niches along the Exploratory Studies Facility (ESF) Main Drift and in the Cross-Drift. The SCM does not predict seepage into waste emplacement drifts under thermal or ambient conditions. Seepage predictions for waste emplacement drifts under ambient conditions will be performed with the SMPA [''Seepage Model for PA Including Drift Collapse'' (BSC 2004 [DIRS 167652])], which inherits the conceptual basis and model-related parameters from the SCM. Seepage during the thermal period is examined separately in the Thermal Hydrologic (TH) Seepage Model [see ''Drift-Scale Coupled Processes (DST and TH Seepage) Models'' (BSC 2004 [DIRS 170338])]. The scope of this work is (1) to evaluate seepage rates measured during liquid-release experiments performed in several niches in the Exploratory Studies Facility (ESF) and in the Cross-Drift, which was excavated for enhanced characterization of the repository block (ECRB); (2) to evaluate air-permeability data measured in boreholes above the niches and the Cross-Drift to obtain the permeability structure for the seepage model

  16. Shallow rainwater lenses in deltaic areas with saline seepage

    Directory of Open Access Journals (Sweden)

    P. G. B. de Louw

    2011-12-01

    Full Text Available In deltaic areas with saline seepage, freshwater availability is often limited to shallow rainwater lenses lying on top of saline groundwater. Here we describe the characteristics and spatial variability of such lenses in areas with saline seepage and the mechanisms that control their occurrence and size. Our findings are based on different types of field measurements and detailed numerical groundwater models applied in the south-western delta of the Netherlands. By combining the applied techniques we could extrapolate measurements at point scale (groundwater sampling, temperature and electrical soil conductivity (TEC-probe measurements, electrical cone penetration tests (ECPT to field scale (continuous vertical electrical soundings (CVES, electromagnetic survey with EM31, and even to regional scale using helicopter-borne electromagnetic measurements (HEM. The measurements show a gradual mixing zone between infiltrating fresh rainwater and upward flowing saline groundwater. The mixing zone is best characterized by the depth of the centre of the mixing zone Dmix, where the salinity is half that of seepage water, and the bottom of the mixing zone Bmix, with a salinity equal to that of the seepage water (Cl-conc. 10 to 16 g l−1. Dmix is found at very shallow depth in the confining top layer, on average at 1.7 m below ground level (b.g.l., while Bmix lies about 2.5 m b.g.l. The model results show that the constantly alternating upward and downward flow at low velocities in the confining layer is the main mechanism of mixing between rainwater and saline seepage and determines the position and extent of the mixing zone (Dmix and Bmix. Recharge, seepage flux, and drainage depth are the controlling factors.

  17. Interaction between hydrocarbon seepage, chemosynthetic communities, and bottom water redox at cold seeps of the Makran accretionary prism: insights from habitat-specific pore water sampling and modeling

    Directory of Open Access Journals (Sweden)

    D. Fischer

    2012-06-01

    Full Text Available The interaction between fluid seepage, bottom water redox, and chemosynthetic communities was studied at cold seeps across one of the world's largest oxygen minimum zones (OMZ located at the Makran convergent continental margin. Push cores were obtained from seeps within and below the core-OMZ with a remotely operated vehicle. Extracted sediment pore water was analyzed for sulfide and sulfate concentrations. Depending on oxygen availability in the bottom water, seeps were either colonized by microbial mats or by mats and macrofauna. The latter, including ampharetid polychaetes and vesicomyid clams, occurred in distinct benthic habitats, which were arranged in a concentric fashion around gas orifices. At most sites colonized by microbial mats, hydrogen sulfide was exported into the bottom water. Where macrofauna was widely abundant, hydrogen sulfide was retained within the sediment.

    Numerical modeling of pore water profiles was performed in order to assess rates of fluid advection and bioirrigation. While the magnitude of upward fluid flow decreased from 11 cm yr−1 to <1 cm yr−1 and the sulfate/methane transition (SMT deepened with increasing distance from the central gas orifice, the fluxes of sulfate into the SMT did not significantly differ (6.6–9.3 mol m−2 yr−1. Depth-integrated rates of bioirrigation increased from 120 cm yr−1 in the central habitat, characterized by microbial mats and sparse macrofauna, to 297 cm yr−1 in the habitat of large and few small vesicomyid clams. These results reveal that chemosynthetic macrofauna inhabiting the outer seep habitats below the core-OMZ efficiently bioirrigate and thus transport sulfate down into the upper 10 to 15 cm of the sediment. In this way the animals deal with the lower upward flux of methane in outer habitats by stimulating rates of anaerobic oxidation of methane (AOM with sulfate high enough to provide

  18. Reactive liquid/liquid extraction of heavy metals from landfill seepage waters. Its characterisation and application

    International Nuclear Information System (INIS)

    Woller, N.

    1994-06-01

    This study demonstrates the applicability of liquid-liquid extraction by means of the commercial complexers LIX26 R and LIX84 R to heavy metal removal from waste waters. The composition of this oil-soluble complex is MeR 2 , where Me denotes Hg 2+ , Cd 2+ , Zn 2+ , Cu 2+ , and Ni 2+ , and R denotes LIX84 R . This composition makes the complex electrically neutral, and all polar groups are located inside the molecule. The extraction efficiency of the complexer LIX84 R for the various metal ions is evident in the succession Cu 2+ , Ni 2+ >> Zn 2+ > Hg 2+ > Cd 2+ . These heavy metal ions are even readily extractable at chloride concentrations of up to 1 mol/l. As the structure of the complexer is that of an oil-soluble surfactant with complexing properties, it accumulates at the phase boundary between oil and water. Measurement of interfacial tension in various solvent systems showed that the polar solvent chloroform permits only a weak accumulation of the complexer (400 nmol/m 2 ), whereas the unpolar solvent kerosine permits greater accumulation specifically on the water side of the phase boundary (1958 nmol/m 2 ). Organic solvents solvate the complexer so well, that it is even removed from the air side of the phase boundary. The differing accumulation of the complexer at the water/oil phase boundary explains the differing increase of phase separation time for polar and unpolar solvents. (orig.) [de

  19. Seepage Model for PA Including Drift Collapse

    International Nuclear Information System (INIS)

    Li, G.; Tsang, C.

    2000-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the predictions and analysis performed using the Seepage Model for Performance Assessment (PA) and the Disturbed Drift Seepage Submodel for both the Topopah Spring middle nonlithophysal and lower lithophysal lithostratigraphic units at Yucca Mountain. These results will be used by PA to develop the probability distribution of water seepage into waste-emplacement drifts at Yucca Mountain, Nevada, as part of the evaluation of the long term performance of the potential repository. This AMR is in accordance with the ''Technical Work Plan for Unsaturated Zone (UZ) Flow and Transport Process Model Report'' (CRWMS M andO 2000 [153447]). This purpose is accomplished by performing numerical simulations with stochastic representations of hydrological properties, using the Seepage Model for PA, and evaluating the effects of an alternative drift geometry representing a partially collapsed drift using the Disturbed Drift Seepage Submodel. Seepage of water into waste-emplacement drifts is considered one of the principal factors having the greatest impact of long-term safety of the repository system (CRWMS M andO 2000 [153225], Table 4-1). This AMR supports the analysis and simulation that are used by PA to develop the probability distribution of water seepage into drift, and is therefore a model of primary (Level 1) importance (AP-3.15Q, ''Managing Technical Product Inputs''). The intended purpose of the Seepage Model for PA is to support: (1) PA; (2) Abstraction of Drift-Scale Seepage; and (3) Unsaturated Zone (UZ) Flow and Transport Process Model Report (PMR). Seepage into drifts is evaluated by applying numerical models with stochastic representations of hydrological properties and performing flow simulations with multiple realizations of the permeability field around the drift. The Seepage Model for PA uses the distribution of permeabilities derived from air injection testing in niches and in the cross drift to

  20. Seepage Model for PA Including Dift Collapse

    Energy Technology Data Exchange (ETDEWEB)

    G. Li; C. Tsang

    2000-12-20

    The purpose of this Analysis/Model Report (AMR) is to document the predictions and analysis performed using the Seepage Model for Performance Assessment (PA) and the Disturbed Drift Seepage Submodel for both the Topopah Spring middle nonlithophysal and lower lithophysal lithostratigraphic units at Yucca Mountain. These results will be used by PA to develop the probability distribution of water seepage into waste-emplacement drifts at Yucca Mountain, Nevada, as part of the evaluation of the long term performance of the potential repository. This AMR is in accordance with the ''Technical Work Plan for Unsaturated Zone (UZ) Flow and Transport Process Model Report'' (CRWMS M&O 2000 [153447]). This purpose is accomplished by performing numerical simulations with stochastic representations of hydrological properties, using the Seepage Model for PA, and evaluating the effects of an alternative drift geometry representing a partially collapsed drift using the Disturbed Drift Seepage Submodel. Seepage of water into waste-emplacement drifts is considered one of the principal factors having the greatest impact of long-term safety of the repository system (CRWMS M&O 2000 [153225], Table 4-1). This AMR supports the analysis and simulation that are used by PA to develop the probability distribution of water seepage into drift, and is therefore a model of primary (Level 1) importance (AP-3.15Q, ''Managing Technical Product Inputs''). The intended purpose of the Seepage Model for PA is to support: (1) PA; (2) Abstraction of Drift-Scale Seepage; and (3) Unsaturated Zone (UZ) Flow and Transport Process Model Report (PMR). Seepage into drifts is evaluated by applying numerical models with stochastic representations of hydrological properties and performing flow simulations with multiple realizations of the permeability field around the drift. The Seepage Model for PA uses the distribution of permeabilities derived from air injection testing in

  1. Seepage/Cement Interactions

    International Nuclear Information System (INIS)

    Carpenter, D.

    2000-01-01

    The Development Plan (CRWMS M andO 1999a) pertaining to this task defines the work scopes and objectives for development of various submodels for the Physical and Chemical Environment Abstraction Model for TSPA-LA. The Development Plan (CRWMS M andO 1999a) for this specific task establishes that an evaluation be performed of the chemical reactions between seepage that has entered the drift and concrete which might be used in the repository emplacement drifts. The Development Plan (CRWMS M andO 1999a) then states that the potential effects of these water/grout reactions on chemical conditions in the drift be assessed factoring in the influence of carbonation and the relatively small amount of grout. This task is also directed at: (1) developing a conceptualization of important cement/seepage interactions and potential impacts on EBS performance, (2) performing a screening analysis to assess the importance of cement/seepage interactions. As the work progresses and evolves on other studies, specifically the Engineered Barrier System: Physical and Chemical Environment (P andCE) Model (in progress), many of the issues associated with items 1 and 2, above, will be assessed. Such issues include: (1) Describing the mineralogy of the specified cementitious grout and its evolution over time. (2) Describing the composition of the water before contacting the grout. (3) Developing reasonable upper-bound estimates for the composition of water contacting grout, emphasizing pH and concentrations for anions such as sulfate. (4) Evaluating the equilibration of cement-influenced water with backfill and gas-phase CO 2 . (5) Developing reasonable-bound estimates for flow rate of affected water into the drift. The concept of estimating an ''upper-bound'' range for reaction between the grout and the seepage, particularly in terms of pH is based on equilibrium being established between the seepage and the grout. For example, this analysis can be based on equilibrium being established as

  2. Seepage water balance of the mixed tailings site IAA Dresden-Coschuetz/Gittersee by means of the two-dimensional model BOWAHALD

    International Nuclear Information System (INIS)

    Helling, C.; Dunger, V.

    1998-01-01

    Uranium mill tailings were deposited in a section of the Kaitzbach valley which was closed by tow dams. The Kaitzbach creek was cased in the area. After the uranium ore processing was finish the dump was used as a municipal waste deposit. The water balance of the IAA Dresden-Coschuetz/Gittersee was only estimated in former works. In this case a modeling of the water balance is very useful in regard to a process orientated quantification of the contaminant transport within the dump as well as into the underground. Simplified and rough estimating methods such as the runoff coefficient concept or rating curves are less suited because of the complexity of the processes. That's why we tried to get a runoff and seepage water balance by means of a two-dimensional water balance model for waste heaps called BOWAHALD. The tailings site IAA Dresden-Coschuetz/Gittersee was divited into several hydrotopes (areas with similar hydrological characteristics). Different exposition and slopes as well as different soils and vegetation were taken into account. The parameter verification is possible due to comparison with available data such hydrochemical and isotopic analysis of seepage water and groundwater. (orig.)

  3. ANL-W 779 pond seepage test

    International Nuclear Information System (INIS)

    Braun, D.R.

    1992-11-01

    The ANL-W 779 sanitary wastewater treatment ponds are located on the Idaho National Engineering Laboratory (INEL), north of the Argonne National Laboratory -- West (ANL-W) site A seepage test was performed for two Argonne National Laboratory -- West (ANL-W) sanitary wastewater treatment ponds, Facility 779. Seepage rates were measured to determine if the ponds are a wastewater land application facility. The common industry standard for wastewater land application facilities is a field-measured seepage rate of one quarter inch per day or greater

  4. Water chemistry, seepage investigation, streamflow, reservoir storage, and annual availability of water for the San Juan-Chama Project, northern New Mexico, 1942-2010

    Science.gov (United States)

    McKean, Sarah E.; Anderholm, Scott K.

    2014-01-01

    The Albuquerque Bernalillo County Water Utility Authority supplements the municipal water supply for the Albuquerque metropolitan area, in central New Mexico, with surface water diverted from the Rio Grande. The U.S. Geological Survey, in cooperation with the Albuquerque Bernalillo County Water Utility Authority, undertook this study in which water-chemistry data and historical streamflow were compiled and new water-chemistry data were collected to characterize the water chemistry and streamflow of the San Juan-Chama Project (SJCP). Characterization of streamflow included analysis of the variability of annual streamflow and comparison of the theoretical amount of water that could have been diverted into the SJCP to the actual amount of water that was diverted for the SJCP. Additionally, a seepage investigation was conducted along the channel between Azotea Tunnel Outlet and the streamflow-gaging station at Willow Creek above Heron Reservoir to estimate the magnitude of the gain or loss in streamflow resulting from groundwater interaction over the approximately 10-mile reach. Generally, surface-water chemistry varied with streamflow throughout the year. Streamflow ranged from high flow to low flow on the basis of the quantity of water diverted from the Rio Blanco, Little Navajo River, and Navajo River for the SJCP. Vertical profiles of the water temperature over the depth of the water column at Heron Reservoir indicated that the reservoir is seasonally stratified. The results from the seepage investigations indicated a small amount of loss of streamflow along the channel. Annual variability in streamflow for the SJCP was an indication of the variation in the climate parameters that interact to contribute to streamflow in the Rio Blanco, Little Navajo River, Navajo River, and Willow Creek watersheds. For most years, streamflow at Azotea Tunnel Outlet started in March and continued for approximately 3 months until the middle of July. The majority of annual streamflow

  5. The impact of land use and land cover changes on solute dynamics in seepage water of soil from karst hillslopes of Southwest China

    International Nuclear Information System (INIS)

    Ding Hu; Lang Yunchao; Liu Congqiang

    2011-01-01

    Land use and land cover changes can cause variations in terrestrial energy, water balance and availability of nutrients. To understand the role of vegetation in regulating the hydrochemistry of karst hillslopes, overland flow and soil seepage water from two hillslopes covered with and without vegetation were studied in the Huanjiang Observation and Research Station for Karst Ecosystems, Guangxi, SW China. Dissolved major ions, as well as isotopic compositions of dissolved inorganic C (DIC) were examined. Water from the vegetated control slope had higher solute concentrations (except NO 3 - ) and lower δ 13 C values than water from the disturbed slope. The dynamics of K + and NO 3 - in soil water sampled in time-sequence from the control slope was different from the disturbed slope. Specifically, K + and NO 3 - concentrations of the control slope decreased gradually over time, while K + and NO 3 - concentrations of the disturbed slope increased, and other ionic concentrations increased in both of the slopes.

  6. Seepage Flow Model and Deformation Properties of Coastal Deep Foundation Pit under Tidal Influence

    Directory of Open Access Journals (Sweden)

    Shu-chen Li

    2018-01-01

    Full Text Available As the coastal region is the most developed region in China, an increasing number of engineering projects are under construction in it in recent years. However, the quality of these projects is significantly affected by groundwater, which is influenced by tidal variations. Therefore, the regional groundwater dynamic characteristics under tidal impact and the spatiotemporal evolution of the seepage field must be considered in the construction of the projects. Then, Boussinesq function was introduced into the research to deduce the seepage equation under tidal influence for the coastal area. To determine the spatiotemporal evolution of the deep foundation pit seepage field and the coastal seepage field evolution model, numerical calculations based on changes in the tidal water level and seepage equation were performed using MATLAB. According to the developed model, the influence of the seepage field on the foundation pit supporting structure in the excavation process was analyzed through numerical simulations. The results of this research could be considered in design and engineering practice.

  7. Geophysical and hydrologic studies of lake seepage variability

    Science.gov (United States)

    Toran, Laura; Nyquist, Jonathan E.; Rosenberry, Donald O.; Gagliano, Michael P.; Mitchell, Natasha; Mikochik, James

    2014-01-01

    Variations in lake seepage were studied along a 130 m shoreline of Mirror Lake NH. Seepage was downward from the lake to groundwater; rates measured from 28 seepage meters varied from 0 to −282 cm/d. Causes of this variation were investigated using electrical resistivity surveys and lakebed sediment characterization. Two-dimensional (2D) resistivity surveys showed a transition in lakebed sediments from outwash to till that correlated with high- and low-seepage zones, respectively. However, the 2D survey was not able to predict smaller scale variations within these facies. In the outwash, fast seepage was associated with permeability variations in a thin (2 cm) layer of sediments at the top of the lakebed. In the till, where seepage was slower than that in the outwash, a three-dimensional resistivity survey mapped a point of high seepage associated with heterogeneity (lower resistivity and likely higher permeability). Points of focused flow across the sediment–water interface are difficult to detect and can transmit a large percentage of total exchange. Using a series of electrical resistivity geophysical methods in combination with hydrologic data to locate heterogeneities that affect seepage rates can help guide seepage meter placement. Improving our understanding of the causes and types of heterogeneity in lake seepage will provide better data for lake budgets and prediction of mass transfer of solutes or contaminants between lakes and groundwater.

  8. Seepage through a hazardous-waste trench cover

    Science.gov (United States)

    Healy, R.W.

    1989-01-01

    Water movement through a waste-trench cover under natural conditions at a low-level radioactive waste disposal site in northwestern Illinois was studied from July 1982 to June 1984, using tensiometers, a moisture probe, and meteorological instruments. Four methods were used to estimate seepage: the Darcy, zero-flux plane, surface-based water-budget, and groundwater-based water-budget methods. Annual seepage estimates ranged from 48 to 216 mm (5-23% of total precipitation), with most seepage occurring in spring. The Darcy method, although limited in accuracy by uncertainty in hydraulic conductivity, was capable of discretizing seepage in space and time and indicated that seepage varied by almost an order of magnitude across the width of the trench. Lowest seepage rates occurred near the center of the cover, where seepage was gradual. Highest rates occurred along the edge of the cover, where seepage was highly episodic, with 84% of the total there being traced to wetting fronts from 28 individual storms. Limitations of the zero-flux-plane method were severe enough for the method to be judged inappropriate for use in this study.Water movement through a waste-trench cover under natural conditions at a low-level radioactive waste disposal site in northwestern Illinois was studied from July 1982 to June 1984, using tensiometers, a moisture probe, and meteorological instruments. Four methods were used to estimate seepage: the Darcy, zero-flux plane, surface-based water-budget, and groundwater-based water-budget methods. Annual seepage estimates ranged from 48 to 216mm (5-23% of total precipitation), with most seepage occurring in spring. The Darcy method, although limited in accuracy by uncertainty in hydraulic conductivity, was capable of discretizing seepage in space and time and indicated that seepage varied by almost an order of magnitude across the width of the trench. Lowest seepage rates occurred near the center of the cover, where seepage was gradual. Highest

  9. POST-PROCESSING ANALYSIS FOR THC SEEPAGE

    International Nuclear Information System (INIS)

    SUN, Y.

    2004-01-01

    This report describes the selection of water compositions for the total system performance assessment (TSPA) model of results from the thermal-hydrological-chemical (THC) seepage model documented in ''Drift-Scale THC Seepage Model'' (BSC 2004 [DIRS 169856]). The selection has been conducted in accordance with ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Post-Processing Analysis for THC Seepage) Report Integration'' (BSC 2004 [DIRS 171334]). This technical work plan (TWP) was prepared in accordance with AP-2.27Q, ''Planning for Science Activities''. Section 1.2.3 of the TWP describes planning information pertaining to the technical scope, content, and management of this report. The post-processing analysis for THC seepage (THC-PPA) documented in this report provides a methodology for evaluating the near-field compositions of water and gas around a typical waste emplacement drift as these relate to the chemistry of seepage, if any, into the drift. The THC-PPA inherits the conceptual basis of the THC seepage model, but is an independently developed process. The relationship between the post-processing analysis and other closely related models, together with their main functions in providing seepage chemistry information for the Total System Performance Assessment for the License Application (TSPA-LA), are illustrated in Figure 1-1. The THC-PPA provides a data selection concept and direct input to the physical and chemical environment (P and CE) report that supports the TSPA model. The purpose of the THC-PPA is further discussed in Section 1.2. The data selection methodology of the post-processing analysis (Section 6.2.1) was initially applied to results of the THC seepage model as presented in ''Drift-Scale THC Seepage Model'' (BSC 2004 [DIRS 169856]). Other outputs from the THC seepage model (DTN: LB0302DSCPTHCS.002 [DIRS 161976]) used in the P and CE (BSC 2004 [DIRS 169860

  10. Geophysical investigation of seepage beneath an earthen dam.

    Science.gov (United States)

    Ikard, S J; Rittgers, J; Revil, A; Mooney, M A

    2015-01-01

    A hydrogeophysical survey is performed at small earthen dam that overlies a confined aquifer. The structure of the dam has not shown evidence of anomalous seepage internally or through the foundation prior to the survey. However, the surface topography is mounded in a localized zone 150 m downstream, and groundwater discharges from this zone periodically when the reservoir storage is maximum. We use self-potential and electrical resistivity tomography surveys with seismic refraction tomography to (1) determine what underlying hydrogeologic factors, if any, have contributed to the successful long-term operation of the dam without apparent indicators of anomalous seepage through its core and foundation; and (2) investigate the hydraulic connection between the reservoir and the seepage zone to determine whether there exists a potential for this success to be undermined. Geophysical data are informed by hydraulic and geotechnical borehole data. Seismic refraction tomography is performed to determine the geometry of the phreatic surface. The hydro-stratigraphy is mapped with the resistivity data and groundwater flow patterns are determined with self-potential data. A self-potential model is constructed to represent a perpendicular profile extending out from the maximum cross-section of the dam, and self-potential data are inverted to recover the groundwater velocity field. The groundwater flow pattern through the aquifer is controlled by the bedrock topography and a preferential flow pathway exists beneath the dam. It corresponds to a sandy-gravel layer connecting the reservoir to the downstream seepage zone. © 2014, National Ground Water Association.

  11. Shallow rainwater lenses in deltaic areas with saline seepage

    NARCIS (Netherlands)

    De Louw, Perry G.B.; Eeman, Sara; Siemon, Bernhard; Voortman, Bernard R.; Gunnink, Jan; Van Baaren, Esther S.; Oude Essink, Gualbert

    2011-01-01

    In deltaic areas with saline seepage, fresh water availability is often limited to shallow rainwater lenses lying on top of saline groundwater. Here we describe the characteristics and spatial variability of such lenses in areas with saline seepage and the mechanisms that control their occurrence

  12. The impact of land use and land cover changes on solute dynamics in seepage water of soil from karst hillslopes of Southwest China

    Energy Technology Data Exchange (ETDEWEB)

    Ding Hu; Lang Yunchao [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46th Guanshui Road, Guiyang 550002 (China); Liu Congqiang, E-mail: liucongqiang@vip.skleg.cn [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46th Guanshui Road, Guiyang 550002 (China)

    2011-06-15

    Land use and land cover changes can cause variations in terrestrial energy, water balance and availability of nutrients. To understand the role of vegetation in regulating the hydrochemistry of karst hillslopes, overland flow and soil seepage water from two hillslopes covered with and without vegetation were studied in the Huanjiang Observation and Research Station for Karst Ecosystems, Guangxi, SW China. Dissolved major ions, as well as isotopic compositions of dissolved inorganic C (DIC) were examined. Water from the vegetated control slope had higher solute concentrations (except NO{sub 3}{sup -}) and lower {delta}{sup 13}C values than water from the disturbed slope. The dynamics of K{sup +} and NO{sub 3}{sup -} in soil water sampled in time-sequence from the control slope was different from the disturbed slope. Specifically, K{sup +} and NO{sub 3}{sup -} concentrations of the control slope decreased gradually over time, while K{sup +} and NO{sub 3}{sup -} concentrations of the disturbed slope increased, and other ionic concentrations increased in both of the slopes.

  13. Solution of AntiSeepage for Mengxi River Based on Numerical Simulation of Unsaturated Seepage

    Science.gov (United States)

    Ji, Youjun; Zhang, Linzhi; Yue, Jiannan

    2014-01-01

    Lessening the leakage of surface water can reduce the waste of water resources and ground water pollution. To solve the problem that Mengxi River could not store water enduringly, geology investigation, theoretical analysis, experiment research, and numerical simulation analysis were carried out. Firstly, the seepage mathematical model was established based on unsaturated seepage theory; secondly, the experimental equipment for testing hydraulic conductivity of unsaturated soil was developed to obtain the curve of two-phase flow. The numerical simulation of leakage in natural conditions proves the previous inference and leakage mechanism of river. At last, the seepage control capacities of different impervious materials were compared by numerical simulations. According to the engineering actuality, the impervious material was selected. The impervious measure in this paper has been proved to be effectible by hydrogeological research today. PMID:24707199

  14. Solution of AntiSeepage for Mengxi River Based on Numerical Simulation of Unsaturated Seepage

    Directory of Open Access Journals (Sweden)

    Youjun Ji

    2014-01-01

    Full Text Available Lessening the leakage of surface water can reduce the waste of water resources and ground water pollution. To solve the problem that Mengxi River could not store water enduringly, geology investigation, theoretical analysis, experiment research, and numerical simulation analysis were carried out. Firstly, the seepage mathematical model was established based on unsaturated seepage theory; secondly, the experimental equipment for testing hydraulic conductivity of unsaturated soil was developed to obtain the curve of two-phase flow. The numerical simulation of leakage in natural conditions proves the previous inference and leakage mechanism of river. At last, the seepage control capacities of different impervious materials were compared by numerical simulations. According to the engineering actuality, the impervious material was selected. The impervious measure in this paper has been proved to be effectible by hydrogeological research today.

  15. Transient Seepage for Levee Engineering Analyses

    Science.gov (United States)

    Tracy, F. T.

    2017-12-01

    Historically, steady-state seepage analyses have been a key tool for designing levees by practicing engineers. However, with the advances in computer modeling, transient seepage analysis has become a potentially viable tool. A complication is that the levees usually have partially saturated flow, and this is significantly more complicated in transient flow. This poster illustrates four elements of our research in partially saturated flow relating to the use of transient seepage for levee design: (1) a comparison of results from SEEP2D, SEEP/W, and SLIDE for a generic levee cross section common to the southeastern United States; (2) the results of a sensitivity study of varying saturated hydraulic conductivity, the volumetric water content function (as represented by van Genuchten), and volumetric compressibility; (3) a comparison of when soils do and do not exhibit hysteresis, and (4) a description of proper and improper use of transient seepage in levee design. The variables considered for the sensitivity and hysteresis studies are pore pressure beneath the confining layer at the toe, the flow rate through the levee system, and a levee saturation coefficient varying between 0 and 1. Getting results for SEEP2D, SEEP/W, and SLIDE to match proved more difficult than expected. After some effort, the results matched reasonably well. Differences in results were caused by various factors, including bugs, different finite element meshes, different numerical formulations of the system of nonlinear equations to be solved, and differences in convergence criteria. Varying volumetric compressibility affected the above test variables the most. The levee saturation coefficient was most affected by the use of hysteresis. The improper use of pore pressures from a transient finite element seepage solution imported into a slope stability computation was found to be the most grievous mistake in using transient seepage in the design of levees.

  16. Cleveland Dam East Abutment : seepage control project

    Energy Technology Data Exchange (ETDEWEB)

    Huber, F.; Siu, D. [Greater Vancouver Regional District, Burnaby, BC (Canada); Ahlfield, S.; Singh, N. [Klohn Crippen Consultants Ltd., Vancouver, BC (Canada)

    2004-09-01

    North Vancouver's 91 meter high Cleveland Dam was built in the 1950s in a deep bedrock canyon to provide a reservoir for potable water to 18 municipalities. Flow in the concrete gravity dam is controlled by a gated spillway, 2 mid-level outlets and intakes and 2 low-level outlets. This paper describes the seepage control measures that were taken at the time of construction as well as the additional measures that were taken post construction to control piezometric levels, seepage and piping and slope instability in the East Abutment. At the time of construction, a till blanket was used to cover the upstream reservoir slope for 200 meters upstream of the dam. A single line grout curtain was used through the overburden from ground surface to bedrock for a distance of 166 meters from the dam to the East Abutment. Since construction, the safety of the dam has been compromised through changes in piezometric pressure, seepage and soil loss. Klohn Crippen Consultants designed a unique seepage control measure to address the instability risk. The project involved excavating 300,000 cubic meters of soil to form a stable slope and construction bench. A vertical wall was constructed to block seepage. The existing seepage control blanket was also extended by 260 meters. The social, environmental and technical issues that were encountered during the rehabilitation project are also discussed. The blanket extension construction has met design requirements and the abutment materials that are most susceptible to internal erosion have been covered by non-erodible blanket materials such as plastic and roller-compacted concrete (RCC). The project was completed on schedule and within budget and has greatly improved the long-term stability of the dam and public safety. 2 refs., 8 figs.

  17. Three Dimensional Seepage Analyses in Mollasadra Dam after Its ...

    African Journals Online (AJOL)

    Michael Horsfall

    constructed on Kor River. pore water pressure in the dam was investigated following its construction and first and second ... Some problems like seepage failure and slope stability are ... In addition, the effects of change in certain input ...

  18. COMPREHENSIVE ANALYSIS ON SEEPAGE AND STRUCTURAL STABILITY OF EARTH-ROCK DAM: A CASE STUDY OF XIQUANYAN DAM IN CHINA

    Directory of Open Access Journals (Sweden)

    Qingqing GUO

    2016-07-01

    Full Text Available Earth-rock dam is commonly used in the high-dam engineering around the world. It has been widely accepted that the analysis on structural and seepage stability plays a very important role, and it is necessary to take into account while designing the earth-rock dam. In performing the analysis of structural and seepage stability, many remarkable methods are available at current stage. However, there are still some important issues remaining unsolved, including: (1 Finite element methods (FEMs is a means of solutions to analysis seepage process, but it is often a difficult task to determine the so-called seepage coefficient, because the common-used water injection test is limited in the practical work due to the high cost and complex procedure. (2 It has long been discussed that the key parameters for structural stability analysis show a significant spatial and temporal variations. It may be partly explained by the inhomogeneous dam-filling during construction work and the developing seepage process. The consequence is that one constant value of the parameter cannot represent the above variations. In this context, we solve the above issues and introduce the solution with a practical earth-rock dam project. For determining the seepage coefficient, the data from the piezo metric tube is used to calculate the potential value, based on which the seepage coefficient can be back-analysed. Then the seepage field, as well as the seepage stability are numerically analysed using the FEM-based SEEP/W program. As to the structural safety, we take into account the spatial and temporal variations of the key parameters, and incorporate the Monte-Carlo simulation method into the commonly used M-P method to calculate the frequency distribution of the obtained structural safety factor. In this way, the structural and seepage safety can be well analysed. This study is also beneficial to provide a mature method and a theoretical insight into the earth-rock dam design

  19. The taming of brackish seepage

    NARCIS (Netherlands)

    Smits, F.J.C.; Olsthoorn, T.; Smulders, L.; van Wielink, I.

    2016-01-01

    In the area that is managed by the waterboard Amstel, Gooi and Vecht, some deep polders are located. Most of them attract large amounts of brackish seepage. This seepage not only contains salt, but also nutriënts.
    Without hydrological intervention, the waterquality in the area would suffer

  20. Evolution Procedure of Multiple Rock Cracks under Seepage Pressure

    Directory of Open Access Journals (Sweden)

    Taoying Liu

    2013-01-01

    Full Text Available In practical geotechnical engineering, most of rock masses with multiple cracks exist in water environment. Under such circumstance, these adjacent cracks could interact with each other. Moreover, the seepage pressure, produced by the high water pressure, can change cracks’ status and have an impact on the stress state of fragile rocks. According to the theory of fracture mechanics, this paper discusses the law of crack initiation and the evolution law of stress intensity factor at the tip of a wing crack caused by compression-shear stress and seepage pressure. Subsequently, considering the interaction of the wing cracks and the additional stress caused by rock bridge damage, this paper proposes the intensity factor evolution equation under the combined action of compression-shear stress and seepage pressure. In addition, this paper analyzes the propagation of cracks under different seepage pressure which reveals that the existence of seepage pressure facilitates the wing crack’s growth. The result indicates that the high seepage pressure converts wing crack growth from stable form to unstable form. Meanwhile, based on the criterion and mechanism for crack initiation and propagation, this paper puts forward the mechanical model for different fracture transfixion failure modes of the crag bridge under the combined action of seepage pressure and compression-shear stress. At the last part, this paper, through investigating the flexibility tensor of the rock mass’s initial damage and its damage evolution in terms of jointed rock mass's damage mechanics, deduces the damage evolution equation for the rock mass with multiple cracks under the combined action of compression-shear stress and seepage pressure. The achievement of this investigation provides a reliable theoretical principle for quantitative research of the fractured rock mass failure under seepage pressure.

  1. New TNX Seepage Basin: Environmental information document

    International Nuclear Information System (INIS)

    Dunaway, J.K.W.; Johnson, W.F.; Kingley, L.E.; Simmons, R.V.; Bledsoe, H.W.

    1986-12-01

    The New TNX Seepage Basin has been in operation at the Savannah River Plant (SRP) since 1980 and is located in the southeastern section of the TNX facility. The basin receives waste from pilot scale tests conducted at TNX in support of the Defense Waste Processing Facility (DWPF) and the plant Separations area. The basin is scheduled for closure after the TNX Effluent Treatment Plant (ETP) begins operation. The basin will be closed pursuant to all applicable state and federal regulations. A statistical analysis of monitoring data indicates elevated levels of sodium and zinc in the groundwater at this site. Closure options considered for the New TNX Seepage Basin include waste removal and closure, no waste removal and closure, and no action. The two predominant pathways for human exposure to chemical contaminants are through surface, subsurface, and atmospheric transport. Modeling calculations were made to determine the risks to human population via these general pathways for the three postulated closure options for the New TNX Seepage Basin. Cost estimates for each closure option at the basin have also been prepared. An evaluation of the environmental impacts from the New TNX Seepage Basin indicate that the relative risks to human health and ecosystems for the postulated closure options are low. The transport of six chemical and one radionuclide constituents through the environmental pathways from the basin were modeled. The maximum chemical carcinogenic risk and the noncarcinogenic risk for the groundwater pathways were from exposure to trichloromethane and nitrate

  2. Silage seepage and water protection. Production and recovery of silage seepage from animal feed and biomass for biogas plants. 7. ed.; Silagesickersaft und Gewaesserschutz. Anfall und Verwertung von Silagesickersaft aus Futtermitteln und Biomasse fuer Biogasanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Spiekers, Hubert [Bayerische Landesanstalt fuer Landwirtschaft (LfL), Freising-Weihenstephan (Germany); Attenberger, Erwin [Bayerisches Landesamt fuer Umwelt, Augsburg (Germany)

    2012-11-15

    The production of silage is now standard and an important basis for a successful milk and beef production. Silage is also needed in agricultural biogas plants as a substrate for energy production. This publication is intended to serve agriculture as a source of information and guidance document for the construction and operation of silos and the administration as an orientating work aid. The factors influencing the accumulation of silage seepage and the possibilities of prevention in silage and silage management are presented and evaluated from environmental and legal perspective. [German] Die Produktion von Silage ist heute Standard und eine wichtige Grundlage fuer eine erfolgreiche Milch- und Rindfleischerzeugung. Silage wird auch in landwirtschaftlichen Biogasanlagen als Substrat zur Energieerzeugung benoetigt. Die vorliegende Publikation soll der Landwirtschaft als Informationsquelle und Handlungsanleitung fuer den Bau und Betrieb von Siloanlagen und der Verwaltung als orientierende Arbeitshilfe dienen. Die Einflussgroessen auf den Anfall an Sickersaeften und die Moeglichkeiten der Vermeidung bei der Silierung und dem Silagemanagement werden dargestellt und aus umwelt- und rechtlicher Sicht bewertet.

  3. Determining TOC in Waters

    Science.gov (United States)

    Kehoe, Thomas J.

    1977-01-01

    The instrumental method for detecting total organic carbon (TOC) in water samples is detailed. The method's limitations are discussed and certain precautions that must be taken are emphasized. The subject of TOC versus COD and BOD is investigated and TOC is determined to be a valid indication of biological demand. (BT)

  4. Calculating earth dam seepage using HYDRUS software applications

    Directory of Open Access Journals (Sweden)

    Jakub Nieć

    2017-06-01

    Full Text Available This paper presents simulations of water seepage within and under the embankment dam of Lake Kowalskie reservoir. The aim of the study was to compare seepage calculation results obtained using analytical and numerical methods. In April 1985, after the first filling of the reservoir to normal storage levels, water leaks was observed at the base of the escarpment, on the air side of the dam. In order to control seepage flow, drainage was performed and additional piezometers installed. To explain the causes of increased pressure in the aquifer under the dam in May 1985 a simplified calculation of filtration was performed. Now, on the basis of archived data from the Department of Hydraulic and Sanitary Engineering using 3D HYDRUS STANDARD software, the conditions of seepage under the dam have been recreated and re-calculated. Piezometric pressure was investigated in three variants of drainage, including drainage before and after modernization.

  5. Study of seepage losses from irrigation canals using radioactive tracer technique

    International Nuclear Information System (INIS)

    Ahmad, M.; Tariq, J.A.; Rashid, A.; Rafiq, M.; Iqbal, N.

    2004-06-01

    Pakistan has an intricate irrigation system comprising a huge network of canals. A significant fraction of water in irrigation canals is lost through seepage, which is further responsible for water logging and salinity in some areas. Government is considering lining of irrigation canals to overcome this twin menace. Due to involvement of huge costs, highly pervious sections where the seepage rate is appreciably high, are needed to be identified for planning and execution of remedial actions to eliminate or minimize seepage losses. The conventional methods of measuring seepage rate from canals are limited to 'ponding' and 'inflow-outflow' methods. The ponding method is usually restricted to small canals because of the costly bulkheads and water requirement, unaffordable closure of canal, non representation of the line source and variation in the rate of seepage loss with time due to the sealing effects of fine sediments settling out. Inaccurate measurement of discharge under field conditions and complication due to diversion do not favour the inflow-outflow method. It is believed that the analytical methods represent the most accurate and convenient means of determining seepage values using accurate insitu hydraulic conductivity of the subsoil determined by radiotracer, geometry of the canal and position of the groundwater. As a practical application, radiotracer experiments were carried out at Rakh branch canal near Sukhiki, District Hafizabad (Punjab) to determine groundwater filtration velocity by single well point dilution technique using Technetium-99m (sup 99m/Tc) radioactive tracer, Hydraulic conductivity (determined from filtration velocity and hydraulic gradient) and canal parameters were used in the parametric equation of parachute curve to estimate the seepage rate. The average seepage rate was 4.05 cubic meter per day per meter length of the canal (equivalent to 3.795 cusec per million square feet or 1.157 cumec per second per million square meter of

  6. H-Area Seepage Basins groundwater monitoring report

    International Nuclear Information System (INIS)

    1992-09-01

    During second quarter 1992, tritium, nitrate, nonvolatile beta, total alpha-emitting radium (radium-224 and radium-226), gross alpha, mercury, lead, tetrachloroethylene, arsenic, and cadmium exceeded the US Environmental Protection Agency Primary Drinking Water Standards (PDWS) in groundwater samples from monitoring wells at the H-Area Seepage Basins (HASB) at the Savannah River Plant. This report gives the results of the analyses of groundwater from the H-Area Seepage Basin

  7. Detection Model for Seepage Behavior of Earth Dams Based on Data Mining

    Directory of Open Access Journals (Sweden)

    Zhenxiang Jiang

    2018-01-01

    Full Text Available Seepage behavior detecting is an important tool for ensuring the safety of earth dams. However, traditional seepage behavior detection methods have used insufficient monitoring data and have mainly focused on single-point measures and local seepage behavior. The seepage behavior of dams is not quantitatively detected based on the monitoring data with multiple measuring points. Therefore, this study uses data mining techniques to analyze the monitoring data and overcome the above-mentioned shortcomings. The massive seepage monitoring data with multiple points are used as the research object. The key information on seepage behavior is extracted using principal component analysis. The correlation between seepage behavior and upstream water level is described as mutual information. A detection model for overall seepage behavior is established. Result shows that the model can completely extract the seepage monitoring data with multiple points and quantitatively detect the overall seepage behavior of earth dams. The proposed method can provide a new and reasonable means of quantitatively detecting the overall seepage behavior of earth dams.

  8. Uranium determination in water

    International Nuclear Information System (INIS)

    Prudenzo, E.J.; Puga, Maria J.; Cerchietti, Maria L.R.; Arguelles, Maria G.

    2005-01-01

    In our laboratory, a procedure has been assessed to determine uranium content of water in normal situations. The method proposed without sample pre-treatment, is simple and rapid. Uranium mass is measured by fluorimetry. For calculation of detection limit (Ld) and quantification level (Lq) we used blank samples and the results were analyzed for different statistical test. The calculation of total propagated uncertainty and sources contribution on real samples are presented. (author)

  9. Infiltration and Seepage Through Fractured Welded Tuff

    International Nuclear Information System (INIS)

    T.A. Ghezzehei; P.F. Dobson; J.A. Rodriguez; P.J. Cook

    2006-01-01

    The Nopal I mine in Pena Blanca, Chihuahua, Mexico, contains a uranium ore deposit within fractured tuff. Previous mining activities exposed a level ground surface 8 m above an excavated mining adit. In this paper, we report results of ongoing research to understand and model percolation through the fractured tuff and seepage into a mined adit both of which are important processes for the performance of the proposed nuclear waste repository at Yucca Mountain. Travel of water plumes was modeled using one-dimensional numerical and analytical approaches. Most of the hydrologic properly estimates were calculated from mean fracture apertures and fracture density. Based on the modeling results, we presented constraints for the arrival time and temporal pattern of seepage at the adit

  10. Infiltration and Seepage Through Fractured Welded Tuff

    Energy Technology Data Exchange (ETDEWEB)

    T.A. Ghezzehei; P.F. Dobson; J.A. Rodriguez; P.J. Cook

    2006-06-20

    The Nopal I mine in Pena Blanca, Chihuahua, Mexico, contains a uranium ore deposit within fractured tuff. Previous mining activities exposed a level ground surface 8 m above an excavated mining adit. In this paper, we report results of ongoing research to understand and model percolation through the fractured tuff and seepage into a mined adit both of which are important processes for the performance of the proposed nuclear waste repository at Yucca Mountain. Travel of water plumes was modeled using one-dimensional numerical and analytical approaches. Most of the hydrologic properly estimates were calculated from mean fracture apertures and fracture density. Based on the modeling results, we presented constraints for the arrival time and temporal pattern of seepage at the adit.

  11. Modeling Coupled Evaporation and Seepage in Ventilated Cavities

    International Nuclear Information System (INIS)

    Ghezzehei, T.; Trautz, R.; Finsterle, S.; Cook, P.; Ahlers, C.

    2004-01-01

    Cavities excavated in unsaturated geological formations are important to activities such as nuclear waste disposal and mining. Such cavities provide a unique setting for simultaneous occurrence of seepage and evaporation. Previously, inverse numerical modeling of field liquid-release tests and associated seepage into cavities were used to provide seepage-related large-scale formation properties by ignoring the impact of evaporation. The applicability of such models was limited to the narrow range of ventilation conditions under which the models were calibrated. The objective of this study was to alleviate this limitation by incorporating evaporation into the seepage models. We modeled evaporation as an isothermal vapor diffusion process. The semi-physical model accounts for the relative humidity, temperature, and ventilation conditions of the cavities. The evaporation boundary layer thickness (BLT) over which diffusion occurs was estimated by calibration against free-water evaporation data collected inside the experimental cavities. The estimated values of BLT were 5 to 7 mm for the open underground drifts and 20 mm for niches closed off by bulkheads. Compared to previous models that neglected the effect of evaporation, this new approach showed significant improvement in capturing seepage fluctuations into open cavities of low relative humidity. At high relative-humidity values (greater than 85%), the effect of evaporation on seepage was very small

  12. Chemical Properties of Pore Water and Sediment at Three Wetland Sites Near the F- and H-Area Seepage Basins, Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Friday, G.P.

    2001-05-15

    In 1980, vegetative stress and arboreal mortality in wetland plant communities down-gradient from the F- and H-Area seepage basins were detected using aerial imagery. By 1988, approximately six acres in H-Area and four acres in F-Area had been adversely impacted. Today, wetland plant communities have become well established at the H-Area tree-kill zone.

  13. Tritium determination in water

    International Nuclear Information System (INIS)

    Gavini, Ricardo M.

    2008-01-01

    An analytical procedure for the determination of tritium in water is described in this paper. The determination is carried out in presence of other radionuclides, such as Fe-55, Ni-63, Mn-54, Zn-65, Co-60, Cd-109, Sr-90, Cs-134 and Cs-137. The method consists in a simple distillation stage prior to measurement by liquid scintillation counting. The samples containing beta and gamma emitters are conditioned with a (NO 3 ) 2 Pb solution and Na(OH) up to pH = 7 - 8. This produces lead hydroxide precipitation that allows fixing volatile elements, which could be transported together with tritium, and may increase the extinction degree of the sample or interfere with the counting process. Special attention must be paid if presence of Fe-55 (E max ∼ 5.95 keV) is suspected as it might not be distinguished from tritium (E max ∼ 18 keV), leading to an overestimation of tritium activity. Different tests were carried to obtain the optimum method conditions, to achieve the purification of the tritium and a pH near to 7 in the distilled. The detection limit (2σ) was 8.0 Bq/l and the distillation performance was 98.3 %. This technique was applied to water samples containing Fe-55 and other gamma radionuclides in 1M hydrochloric acid media in successive Environmental Measurements Laboratory (EML), U.S. Department of Energy (DOE) intercomparison programs. The results obtained were very satisfactory and are presented in this paper. (author)

  14. Mapping seepage through the River Reservoir Dam near Eagar, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Rollins, P.

    2005-06-30

    This article describes the actions taken to address an unusual amount of water seepage from the left abutment weir-box of the River Reservoir dam built in 1896 near Eagar, Arizona. Upon noting the seepage in March 2004, the operator, Round Valley Water Users Association, contacted the State of Arizona who funded the investigation and subsequent remediation activities through an emergency fund. The dam was originally built with local materials and did not include a clay core. It was modified at least four times. The embankment sits on basalt bedrock and consists of clayey soils within a rock-fill shell. AquaTrack technology developed by Willowstick Technologies was used to assess the deteriorating situation. AquaTrack uses a low voltage, low amperage audio-frequency electrical current to energize the groundwater or seepage. This made it possible to follow the path of groundwater between the electrodes. A magnetic field was created which made it possible to locate and map the field measurements. The measured magnetic field data was processed, contoured and correlated to other hydrogeologic information. This identified the extent and preferential flow paths of the seepage. The survey pinpointed the area with the greatest leakage in both the horizontal and vertical directions. Fluorescent dyes were also used for tracer work to confirm previous findings that showed a serious seepage problem. The water of the reservoir was lowered to perform remedial measures to eliminate the risk of immediate failure. Funding for a more permanent repair is pending. 10 figs.

  15. Air Compressibility Effect on Bouwer and Rice Seepage Meter.

    Science.gov (United States)

    Peng, Xin; Zhan, Hongbin

    2017-11-01

    Measuring a disconnected streambed seepage flux using a seepage meter can give important streambed information and help understanding groundwater-surface water interaction. In this study, we provide a correction for calculating the seepage flux rate with the consideration of air compressibility inside the manometer of the Bouwer and Rice seepage meter. We notice that the effect of air compressibility in the manometer is considerably larger when more air is included in the manometer. We find that the relative error from neglecting air compressibility can be constrained within 5% if the manometer of the Bouwer and Rice seepage meter is shorter than 0.8 m and the experiment is done in a suction mode in which air is pumped out from the manometer before the start of measurement. For manometers longer than 0.8 m, the relative error will be larger than 5%. It may be over 10% if the manometer height is longer than 1.5 m and the experiment is done in a no-suction mode, in which air is not pumped out from the manometer before the start of measurement. © 2017, National Ground Water Association.

  16. Seepage into an Underground Opening Constructed in Unsaturated Fractured Rock Under Evaporative Conditions, RPR 29013(C)

    International Nuclear Information System (INIS)

    Trautz, R. C.; Wang, Joseph S. Y.

    2001-01-01

    Liquid-release tests, performed in boreholes above an underground opening constructed in unsaturated fractured rock, are used in this study to evaluate seepage into a waste emplacement drift. Evidence for the existence of a capillary barrier at the ceiling of the drift is presented, based on field observations (including spreading of the wetting front across the ceiling and water movement up fractures exposed in the ceiling before seepage begins). The capillary barrier mechanism has the potential to divert water around the opening, resulting in no seepage when the percolation flux is at or below the seepage threshold flux. Liquid-release tests are used to demonstrate that a seepage threshold exists and to measure the magnitude of the seepage threshold flux for three test zones that seeped. The seepage data are interpreted using analytical techniques to estimate the test-specific strength of the rock capillary forces (α -1 ) that prevent water from seeping into the drift. Evaporation increases the seepage threshold flux making it more difficult for water to seep into the drift and producing artificially inflated α -1 values. With adjustments for evaporation, the minimum test-specific threshold is 1,600 mm/yr with a corresponding α -1 of 0.027 m

  17. Forward modeling of seepage of reservoir dam based on ground penetrating radar

    Directory of Open Access Journals (Sweden)

    Xueli WU

    2017-08-01

    Full Text Available The risk of the reservoir dam seepage will bring the waste of water resources and the loss of life and property. The ground penetrating radar (GPR is designed as a daily inspection system of dams to improve the existing technology which can't determine the actual situation of the dam seepage tunnel coordinates. The finite difference time domain (FDTD is used to solve the Yee's grids discreatization in two-dimensional space, and its electromagnetic distribution equation is obtained as well. Based on the actual structure of reservoir dam foundation, the ideal model of air layer, concrete layer, clay layer and two water seepage holes is described in detail, and the concrete layer interference model with limestone interference point is established. The system architecture is implemented by using MATLAB, and the forward modeling is performed. The results indicate that ground penetrating radar can be used for deep target detection. Through comparing the detection spectrum of three kinds of frequency electromagnetic wave by changing the center frequency of the GPR electromagnetic wave of 50 MHz, 100 MHz and 200 MHz, it is concluded that the scanning result is more accurate at 100 MHz. At the same time, the simulation results of the interference model show that this method can be used for the detection of complex terrain.

  18. Mapping on Slope Seepage Problem using Electrical Resistivity Imaging (ERI)

    Science.gov (United States)

    Hazreek, Z. A. M.; Nizam, Z. M.; Aziman, M.; Dan, M. F. Md; Shaylinda, M. Z. N.; Faizal, T. B. M.; Aishah, M. A. N.; Ambak, K.; Rosli, S.; Rais, Y.; Ashraf, M. I. M.; Alel, M. N. A.

    2018-04-01

    The stability of slope may influenced by several factors such as its geomaterial properties, geometry and environmental factors. Problematic slope due to seepage phenomenon will influenced the slope strength thus promoting to its failure. In the past, slope seepage mapping suffer from several limitation due to cost, time and data coverage. Conventional engineering tools to detect or mapped the seepage on slope experienced those problems involving large and high elevation of slope design. As a result, this study introduced geophysical tools for slope seepage mapping based on electrical resistivity method. Two spread lines of electrical resistivity imaging were performed on the slope crest using ABEM SAS 4000 equipment. Data acquisition configuration was based on long and short arrangement, schlumberger array and 2.5 m of equal electrode spacing interval. Raw data obtained from data acquisition was analyzed using RES2DINV software. Both of the resistivity results show that the slope studied consists of three different anomalies representing top soil (200 – 1000 Ωm), perched water (10 – 100 Ωm) and hard/dry layer (> 200 Ωm). It was found that seepage problem on slope studied was derived from perched water zones with electrical resistivity value of 10 – 100 Ωm. Perched water zone has been detected at 6 m depth from the ground level with varying thickness at 5 m and over. Resistivity results have shown some good similarity output with reference to borehole data, geological map and site observation thus verified the resistivity results interpretation. Hence, this study has shown that the electrical resistivity imaging was applicable in slope seepage mapping which consider efficient in term of cost, time, data coverage and sustainability.

  19. Natural gas seepage from a dug well in Gemerska Panica

    International Nuclear Information System (INIS)

    Milicka, J.; Pereszlenyi, M.; Masaryk, P.

    1997-01-01

    On July 20 1993, a seepage of inflammable natural gas was reported by workers of the Slovak Gas Industry enterprise (SPP) to the Oil and Gas Research and Prospecting (VVNP). Therefore, the locality was visited with the aim to evaluate the current situation, to take rock and water samples for for chemical analysis, to survey the vicinity of Gemerska Panica and to prepare a preliminary oil-geological evaluation of the area, with a suggestion of further prospecting. At the same time, the seepage of inflammable natural gas was reported to the District Mining Office in Spisska Nova Ves. (authors)

  20. An evaluation of seepage gains and losses in Indian Creek Reservoir, Ada County, Idaho, April 2010–November 2011

    Science.gov (United States)

    Williams, Marshall L.; Etheridge, Alexandra B.

    2013-01-01

    The U.S. Geological Survey, in cooperation with the Idaho Department of Water Resources, conducted an investigation on Indian Creek Reservoir, a small impoundment in east Ada County, Idaho, to quantify groundwater seepage into and out of the reservoir. Data from the study will assist the Idaho Water Resources Department’s Comprehensive Aquifer Management Planning effort to estimate available water resources in Ada County. Three independent methods were utilized to estimate groundwater seepage: (1) the water-budget method; (2) the seepage-meter method; and (3) the segmented Darcy method. Reservoir seepage was quantified during the periods of April through August 2010 and February through November 2011. With the water-budget method, all measureable sources of inflow to and outflow from the reservoir were quantified, with the exception of groundwater; the water-budget equation was solved for groundwater inflow to or outflow from the reservoir. The seepage-meter method relies on the placement of seepage meters into the bottom sediments of the reservoir for the direct measurement of water flux across the sediment-water interface. The segmented-Darcy method utilizes a combination of water-level measurements in the reservoir and in adjacent near-shore wells to calculate water-table gradients between the wells and the reservoir within defined segments of the reservoir shoreline. The Darcy equation was used to calculate groundwater inflow to and outflow from the reservoir. Water-budget results provided continuous, daily estimates of seepage over the full period of data collection, while the seepage-meter and segmented Darcy methods provided instantaneous estimates of seepage. As a result of these and other difference in methodologies, comparisons of seepage estimates provided by the three methods are considered semi-quantitative. The results of the water-budget derived estimates of seepage indicate seepage to be seasonally variable in terms of the direction and magnitude

  1. Potential Antifreeze Compounds in Present-Day Martian Seepage Groundwater

    Directory of Open Access Journals (Sweden)

    Jiin-Shuh Jean

    2008-01-01

    Full Text Available Is the recently found seepage groundwater on Mars pure H2O, or mixed with salts and other antifreeze compounds? Given the surface conditions of Mars, it is unlikely that pure water could either exist in its liquid state or have shaped Mars¡¦ fluid erosional landforms (gullies, channels, and valley networks. More likely is that Mars¡¦ seepage groundwater contains antifreeze and salt compounds that resist freezing and suppress evaporation. This model better accounts for Mars¡¦ enigmatic surface erosion. This paper suggests 17 antifreeze compounds potentially present in Martian seepage groundwater. Given their liquid state and physical properties, triethylene glycol, diethylene glycol, ethylene glycol, and 1,3-propylene glycol are advanced as the most likely candidate compounds. This paper also explores how a mixing of glycol or glycerol with salts in the Martian seepage groundwater may have lowered water¡¦s freezing point and raised its boiling point, with consequences that created fluid gully and channel erosion. Ethylene glycol and related hydrocarbon compounds have been identified in Martian and other interstellar meteorites. We suggest that these compounds and their proportions to water be included for detection in future explorations.

  2. Liquid chromatographic determination of water

    Science.gov (United States)

    Fortier, N.E.; Fritz, J.S.

    1990-11-13

    A sensitive method for the determination of water in the presence of common interferences is presented. The detection system is based on the effect of water on the equilibrium which results from the reaction aryl aldehydes, such as cinnamaldehyde and methanol in the eluent to form cinnamaldehyde dimethylacetal, plus water. This equilibrium is shifted in a catalytic atmosphere of a hydrogen ion form past column reactor. The extent of the shift and the resulting change in absorbance are proportional to the amount of water present. 1 fig.

  3. 基于压水试验的杨村煤矿底板断层带渗流性质研究%Research on Seepage Characteristics of Floor Fault Zone Based on Water Injection Test in Yangcun Coal Mine

    Institute of Scientific and Technical Information of China (English)

    邵明喜; 官云章; 曹思文; 张鑫; 刘近国; 吕先阳; 孙晓倩

    2016-01-01

    In order to study the seepage characteristics of the floor fault zone in Yangcun Mine, water injection test method was used for the measurement of Fault 5 and a number of measured data were obtained. Analysis results showed that the permeability of this fault was bad and its permeation resistance was relatively strong in the original state. Four water injection tests on this fault were carried out, and from the comparison of the permeability changing curves in four water injection tests it was found out that the repeated water injection can lead failure of the fault zone, which in turn improved its permeability. The relation between test pressure and flow rate(p—Q) of F5 fault was a dilation or erosion type, the fissures in this fault zone developed and many filling materials existed in it, so it has stronger resistance to seepage.%为研究杨村煤矿底板断层带的渗流性质,采用现场压水试验方法对底板F5断层进行了测试并获取了大量的实测数据,分析结果表明:该断层在原始状态下渗流能力较差,阻渗性较强。对该断层进行了4次压水试验,对比4次压水试验的渗透系数变化曲线可知,重复压水可导致断层带明显渗透破坏,由此造成其导渗性能的进一步增强;F5断层带两段压渗试验压力和流量关系( p—Q )为扩张或冲蚀型,该断层带裂隙发育,裂隙中间有较多充填物,阻渗能力较好。

  4. Shallow bedrock limits groundwater seepage-based headwater climate refugia

    Science.gov (United States)

    Briggs, Martin A.; Lane, John W.; Snyder, Craig D.; White, Eric A.; Johnson, Zachary; Nelms, David L.; Hitt, Nathaniel P.

    2018-01-01

    Groundwater/surface-water exchanges in streams are inexorably linked to adjacent aquifer dynamics. As surface-water temperatures continue to increase with climate warming, refugia created by groundwater connectivity is expected to enable cold water fish species to survive. The shallow alluvial aquifers that source groundwater seepage to headwater streams, however, may also be sensitive to seasonal and long-term air temperature dynamics. Depth to bedrock can directly influence shallow aquifer flow and thermal sensitivity, but is typically ill-defined along the stream corridor in steep mountain catchments. We employ rapid, cost-effective passive seismic measurements to evaluate the variable thickness of the shallow colluvial and alluvial aquifer sediments along a headwater stream supporting cold water-dependent brook trout (Salvelinus fontinalis) in Shenandoah National Park, VA, USA. Using a mean depth to bedrock of 2.6 m, numerical models predicted strong sensitivity of shallow aquifer temperature to the downward propagation of surface heat. The annual temperature dynamics (annual signal amplitude attenuation and phase shift) of potential seepage sourced from the shallow modeled aquifer were compared to several years of paired observed stream and air temperature records. Annual stream water temperature patterns were found to lag local air temperature by ∼8–19 d along the stream corridor, indicating that thermal exchange between the stream and shallow groundwater is spatially variable. Locations with greater annual signal phase lag were also associated with locally increased amplitude attenuation, further suggestion of year-round buffering of channel water temperature by groundwater seepage. Numerical models of shallow groundwater temperature that incorporate regional expected climate warming trends indicate that the summer cooling capacity of this groundwater seepage will be reduced over time, and lower-elevation stream sections may no longer serve as larger

  5. Modelling stream aquifer seepage in an alluvial aquifer: an improved loosing-stream package for MODFLOW

    Science.gov (United States)

    Osman, Yassin Z.; Bruen, Michael P.

    2002-07-01

    Seepage from a stream, which partially penetrates an unconfined alluvial aquifer, is studied for the case when the water table falls below the streambed level. Inadequacies are identified in current modelling approaches to this situation. A simple and improved method of incorporating such seepage into groundwater models is presented. This considers the effect on seepage flow of suction in the unsaturated part of the aquifer below a disconnected stream and allows for the variation of seepage with water table fluctuations. The suggested technique is incorporated into the saturated code MODFLOW and is tested by comparing its predictions with those of a widely used variably saturated model, SWMS_2D simulating water flow and solute transport in two-dimensional variably saturated media. Comparisons are made of both seepage flows and local mounding of the water table. The suggested technique compares very well with the results of variably saturated model simulations. Most currently used approaches are shown to underestimate the seepage and associated local water table mounding, sometimes substantially. The proposed method is simple, easy to implement and requires only a small amount of additional data about the aquifer hydraulic properties.

  6. Determination of heavy water in heavy water - light water mixtures

    International Nuclear Information System (INIS)

    Sanhueza M, A.

    1986-01-01

    A description about experimental methodology to determine isotopic composition of heavy water - light water mixtures is presented. The employed methods are Nuclear Magnetic Resonance Spectroscopy, for measuring heavy water concentrations from 0 to 100% with intervals of 10% approx., and mass Spectrometry, for measuring heavy water concentrations from 0.1 to 1% with intervals of 0.15% approx., by means of an indirect method of Dilution. (Author)

  7. SEEPAGE INTO DRIFTS IN UNSATRUATED FRACTURED ROCK AT YUCCA MOUNTAIN

    International Nuclear Information System (INIS)

    JENS BIRHOLZER; GUOMIN LI; CHIN-FU TSANG; YVONNE TSANG

    1998-01-01

    An important issue for the long-term performance of underground nuclear waste repositories is the rate of seepage into the waste emplacement drifts. A prediction of the future seepage rate is particularly complicated for the potential repository site at Yucca Mountain, Nevada, as it is located in thick, partially saturated, fractured tuff formations. The long-term situation in the drifts several thousand years after waste emplacement will be characterized by a relative humidity level close to or equal to 100%. as the drifts will be sealed and unventilated, and the waste packages will have cooled. The underground tunnels will then act as capillary barriers for the unsaturated flow, ideally diverting water around them, if the capillary forces are stronger than gravity and viscous forces. Seepage into the drifts will only be possible if the hydraulic pressure in the rock close to the drift walls increases to positive values; i.e., the flow field becomes locally saturated. In the present work, we have developed and applied a methodology to study the potential rate of seepage into underground cavities embedded in a variably saturated, heterogeneous fractured rock formation. The fractured rock mass is represented as a stochastic continuum where the fracture permeabilities vary by several orders of magnitude. Three different realizations of random fracture permeability fields are generated, with the random permeability structure based on extensive fracture mapping, borehole video analysis, and in-situ air permeability testing. A 3-D numerical model is used to simulate the heterogeneous steady-state flow field around the drift, with the drift geometry explicitly represented within the numerical discretization grid. A variety of flow scenarios are considered assuming present-day and future climate conditions at Yucca Mountain. The numerical study is complemented by theoretical evaluations of the drift seepage problem, using stochastic perturbation theory to develop a better

  8. Heterogeneous seepage at the Nopal I natural analogue site, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, Patrick F.; Cook, Paul J.; Ghezzehei, Teamrat A.; Rodriguez, J. Alfredo; Villalba, Lourdes; de la Garza, Rodrigo

    2008-10-25

    An integrated field, laboratory, and modeling study of the Pena Blanca (Chihuahua, Mexico) natural analogue site is being conducted to evaluate processes that control the mobilization and transport of radionuclides from a uranium ore deposit. One component of this study is an evaluation of the potential for radionuclide transport through the unsaturated zone (UZ) via a seepage study in an adit at the Nopal I uranium mine, excavated 10 m below a mined level surface. Seasonal rainfall on the exposed level surface infiltrates into the fractured rhyolitic ash-flow tuff and seeps into the adit. An instrumented seepage collection system and local automated weather station permit direct correlation between local precipitation events and seepage within the Nopal I +00 adit. Monitoring of seepage within the adit between April 2005 and December 2006 indicates that seepage is highly heterogeneous with respect to time, location, and quantity. Within the back adit area, a few zones where large volumes of water have been collected are linked to fast flow path fractures (0-4 h transit times) presumably associated with focused flow. In most locations, however, there is a 1-6 month time lag between major precipitation events and seepage within the adit, with longer residence times observed for the front adit area. Seepage data obtained from this study will be used to provide input to flow and transport models being developed for the Nopal I hydrogeologic system.

  9. Heterogeneous seepage at the Nopal I natural analogue site, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Dobson, Patrick F.; Cook, Paul J.; Ghezzehei, Teamrat A.; Rodriguez, J. Alfredo; Villalba, Lourdes; de la Garza, Rodrigo

    2008-01-01

    An integrated field, laboratory, and modeling study of the Pena Blanca (Chihuahua, Mexico) natural analogue site is being conducted to evaluate processes that control the mobilization and transport of radionuclides from a uranium ore deposit. One component of this study is an evaluation of the potential for radionuclide transport through the unsaturated zone (UZ) via a seepage study in an adit at the Nopal I uranium mine, excavated 10 m below a mined level surface. Seasonal rainfall on the exposed level surface infiltrates into the fractured rhyolitic ash-flow tuff and seeps into the adit. An instrumented seepage collection system and local automated weather station permit direct correlation between local precipitation events and seepage within the Nopal I +00 adit. Monitoring of seepage within the adit between April 2005 and December 2006 indicates that seepage is highly heterogeneous with respect to time, location, and quantity. Within the back adit area, a few zones where large volumes of water have been collected are linked to fast flow path fractures (0-4 h transit times) presumably associated with focused flow. In most locations, however, there is a 1-6 month time lag between major precipitation events and seepage within the adit, with longer residence times observed for the front adit area. Seepage data obtained from this study will be used to provide input to flow and transport models being developed for the Nopal I hydrogeologic system.

  10. Polyelectrolyte determination in drinking water

    African Journals Online (AJOL)

    try as there are no readily available methods for the determination of residual polyelectrolyte concentration. This study aims at ... quate, making the need to quantify them more critical (Fielding,. 1999). ... decisions and actions are sometimes required in the environ- ... were conducted on both distilled and real water systems.

  11. Three-dimensional imaging, change detection, and stability assessment during the centerline trench levee seepage experiment using terrestrial light detection and ranging technology, Twitchell Island, California, 2012

    Science.gov (United States)

    Bawden, Gerald W.; Howle, James; Bond, Sandra; Shriro, Michelle; Buck, Peter

    2014-01-01

    A full scale field seepage test was conducted on a north-south trending levee segment of a now bypassed old meander belt on Twitchell Island, California, to understand the effects of live and decaying root systems on levee seepage and slope stability. The field test in May 2012 was centered on a north-south trench with two segments: a shorter control segment and a longer seepage test segment. The complete length of the trench area measured 40.4 meters (m) near the levee centerline with mature trees located on the waterside and landside of the levee flanks. The levee was instrumented with piezometers and tensiometers to measure positive and negative porewater pressures across the levee after the trench was flooded with water and held at a constant hydraulic head during the seepage test—the results from this component of the experiment are not discussed in this report. We collected more than one billion three-dimensional light detection and ranging (lidar) data points before, during, and after the centerline seepage test to assess centimeter-scale stability of the two trees and the levee crown. During the seepage test, the waterside tree toppled (rotated 20.7 degrees) into the water. The landside tree rotated away from the levee by 5 centimeters (cm) at a height of 2 m on the tree. The paved surface of the levee crown had three regions that showed subsidence on the waterside of the trench—discussed as the northern, central, and southern features. The northern feature is an elongate region that subsided 2.1 cm over an area with an average width of 1.35 m that extends 15.8 m parallel to the trench from the northern end of the trench to just north of the trench midpoint, and is associated with a crack 1 cm in height that formed during the seepage test on the trench wall. The central subsidence feature is a semicircular region on the waterside of the trench that subsided by as much as 6.2 cm over an area 3.4 m wide and 11.2 m long. The southern feature is an elongate

  12. H-Area Seepage Basins groundwater monitoring report

    International Nuclear Information System (INIS)

    Thompson, C.Y.

    1992-06-01

    During first quarter 1992, tritium, nitrate, nonvolatile beta, total alpha-emitting radium (radium-224 and radium-226), gross alpha, antimony, mercury, lead, tetrachloroethylene, arsenic, and cadmium exceeded the US Environmental Protection Agency Primary Drinking Water Standards (PDWS) in groundwater samples from monitoring wells at the H-Area Seepage Basins (HASB) at the Savannah River Site. This report presents and discusses the groundwater monitoring results in the H-Area for first quarter 1992

  13. Seepage into drifts with mechanical degradation

    International Nuclear Information System (INIS)

    Li, Guomin; Tsang, Chin-Fu

    2002-01-01

    Seepage into drifts in unsaturated tuff is an important issue for the long-term performance of the potential nuclear waste repository at Yucca Mountain, Nevada. Drifts in which waste packages will potentially be emplaced are subject to degradation in the form of rockfall from the drift ceiling induced by stress relief, seismic, or thermal effects. The objective of this study is to calculate seepage rates for various drift-degradation scenarios and for different values of percolation flux for the Topopah Spring middle nonlithophysal (Tptpmn) and the Topopah Spring lower lithophysal (Tptpll) units. Seepage calculations are conducted by (1) defining a heterogeneous permeability model on the drift scale that is consistent with field data, (2) selecting calibrated parameters associated with the Tptpmn and Tptpll units, and (3) simulating seepage on detailed degraded-drift profiles, which were obtained from a separate rock mechanics engineering analysis. The simulation results indicate (1) that the seepage threshold (i.e., the percolation flux at which seepage first occurs) is not significantly changed by drift degradation, and (2) the degradation-induced increase in seepage above the threshold is influenced more by the shape of the cavity created by rockfall than the rockfall volume

  14. Impact of Quaternary Climate on Seepage at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    J.F. Whelan; J.B. Paces; L.A. Neymark; A.K. Schmitt; M. Grove

    2006-01-01

    Uranium-series ages, oxygen-isotopic compositions, and uranium contents were determined in outer growth layers of opal and calcite from 0.5- to 3-centimeter-thick mineral coatings hosted by lithophysal cavities in the unsaturated zone at Yucca Mountain, Nevada, the proposed site of a permanent repository for high-level radioactive waste. Micrometer-scale growth layering in the minerals was imaged using a cathodoluminescence detector on a scanning electron microscope. Determinations of the chemistry, ages, and delta oxygen-18 values of the growth layers were conducted by electron microprobe analysis and secondary ion mass spectrometry techniques at spatial resolutions of 1 to about 20 micrometers ((micro)m) and 25 to 40 micrometers, respectively. Growth rates for the last 300 thousand years (k.y.) calculated from about 300 new high-resolution uranium-series ages range from approximately 0.5 to 1.5 (micro)m/k.y. for 1- to 3-centimeter-thick coatings, whereas coatings less than about I-centimeter-thick have growth rates less than 0.5 (micro)m/k.y. At the depth of the proposed repository, correlations of uranium concentration and delta oxygen-18 values with regional climate records indicate that unsaturated zone percolation and seepage water chemistries have responded to changes in climate during the last several hundred thousand years

  15. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    International Nuclear Information System (INIS)

    Dixon, P.

    2004-01-01

    The purpose of this Model Report (REV02) is to document the unsaturated zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrological-chemical (THC) processes on UZ flow and transport. This Model Report has been developed in accordance with the ''Technical Work Plan for: Performance Assessment Unsaturated Zone'' (Bechtel SAIC Company, LLC (BSC) 2002 [160819]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this Model Report in Section 1.12, Work Package AUZM08, ''Coupled Effects on Flow and Seepage''. The plan for validation of the models documented in this Model Report is given in Attachment I, Model Validation Plans, Section I-3-4, of the TWP. Except for variations in acceptance criteria (Section 4.2), there were no deviations from this TWP. This report was developed in accordance with AP-SIII.10Q, ''Models''. This Model Report documents the THC Seepage Model and the Drift Scale Test (DST) THC Model. The THC Seepage Model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral alteration on flow in rocks surrounding drifts. The DST THC model is a drift-scale process model relying on the same conceptual model and much of the same input data (i.e., physical, hydrological, thermodynamic, and kinetic) as the THC Seepage Model. The DST THC Model is the primary method for validating the THC Seepage Model. The DST THC Model compares predicted water and gas compositions, as well as mineral alteration patterns, with observed data from the DST. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal-loading conditions, and predict the evolution of mineral alteration and fluid chemistry around potential waste emplacement drifts. The DST THC Model is used solely for the validation of the THC

  16. Effects of recharge, Upper Floridan aquifer heads, and time scale on simulated ground-water exchange with Lake Starr, a seepage lake in central Florida

    Science.gov (United States)

    Swancar, Amy; Lee, Terrie Mackin

    2003-01-01

    Lake Starr and other lakes in the mantled karst terrain of Florida's Central Lake District are surrounded by a conductive surficial aquifer system that receives highly variable recharge from rainfall. In addition, downward leakage from these lakes varies as heads in the underlying Upper Floridan aquifer change seasonally and with pumpage. A saturated three-dimensional finite-difference ground-water flow model was used to simulate the effects of recharge, Upper Floridan aquifer heads, and model time scale on ground-water exchange with Lake Starr. The lake was simulated as an active part of the model using high hydraulic conductivity cells. Simulated ground-water flow was compared to net ground-water flow estimated from a rigorously derived water budget for the 2-year period August 1996-July 1998. Calibrating saturated ground-water flow models with monthly stress periods to a monthly lake water budget will result in underpredicting gross inflow to, and leakage from, ridge lakes in Florida. Underprediction of ground-water inflow occurs because recharge stresses and ground-water flow responses during rainy periods are averaged over too long a time period using monthly stress periods. When inflow is underestimated during calibration, leakage also is underestimated because inflow and leakage are correlated if lake stage is maintained over the long term. Underpredicted leakage reduces the implied effect of ground-water withdrawals from the Upper Floridan aquifer on the lake. Calibrating the weekly simulation required accounting for transient responses in the water table near the lake that generated the greater range of net ground-water flow values seen in the weekly water budget. Calibrating to the weekly lake water budget also required increasing the value of annual recharge in the nearshore region well above the initial estimate of 35 percent of the rainfall, and increasing the hydraulic conductivity of the deposits around and beneath the lake. To simulate the total

  17. Determination of radium in water

    Energy Technology Data Exchange (ETDEWEB)

    Hohorst, F.A.; Huntley, M.W.; Hartenstein, S.D.

    1995-10-01

    These detailed work instructions (DWIs) are tailored for the analysis of radium-226 and radium-228 in drinking water supplies from ground water and surface water sources and composites derived from them. The instructions have been adapted from several sources, including a draft EPA method. One objective was to minimize the generation of mixed wastes. Quantitative determinations of actinium-228 are made at 911 keV. The minimum detection level (MDL) for the gamma spectrometric measurements at this energy vary with matrix, volume, geometry, detector, background, and counting statistics. The range of MDL`s for current detectors is 0.07 to 0.5 Bq/sample. Quantitative determinations of radium-226 are made by counting the high energy alpha particles which radium-226 progeny emit using liquid scintillation counting (LSC). The minimum detectable activity (MDA) is 3.8 E-3 Bq/sample. The maximum concentration which may be counted on available instruments without dilution is about 2 E + 5 Bq/sample. Typically, this determination of radium in a 2 L sample has a yield of 80%. If radium-228 is determined using a 16 h count after 50 h grow-in, the typical MDL is 1 E-9 to 8 E-9 {mu}Ci/mL (1 to 8 pCi/L). If radium-226 is determined using a 2.5 h count after 150 h grow-in, the typical MDA is about 1 E-10 {mu}Ci/mL (0. 1 pCi/L).

  18. Determination of radium in water

    International Nuclear Information System (INIS)

    Hohorst, F.A.; Huntley, M.W.; Hartenstein, S.D.

    1995-10-01

    These detailed work instructions (DWIs) are tailored for the analysis of radium-226 and radium-228 in drinking water supplies from ground water and surface water sources and composites derived from them. The instructions have been adapted from several sources, including a draft EPA method. One objective was to minimize the generation of mixed wastes. Quantitative determinations of actinium-228 are made at 911 keV. The minimum detection level (MDL) for the gamma spectrometric measurements at this energy vary with matrix, volume, geometry, detector, background, and counting statistics. The range of MDL's for current detectors is 0.07 to 0.5 Bq/sample. Quantitative determinations of radium-226 are made by counting the high energy alpha particles which radium-226 progeny emit using liquid scintillation counting (LSC). The minimum detectable activity (MDA) is 3.8 E-3 Bq/sample. The maximum concentration which may be counted on available instruments without dilution is about 2 E + 5 Bq/sample. Typically, this determination of radium in a 2 L sample has a yield of 80%. If radium-228 is determined using a 16 h count after 50 h grow-in, the typical MDL is 1 E-9 to 8 E-9 μCi/mL (1 to 8 pCi/L). If radium-226 is determined using a 2.5 h count after 150 h grow-in, the typical MDA is about 1 E-10 μCi/mL (0. 1 pCi/L)

  19. Methane seepage along the Hikurangi Margin of New Zealand : geochemical and physical data from the water column, sea surface and atmosphere

    OpenAIRE

    Faure, Kevin; Greinert, Jens; Schneider, Jens; McGinnis, Daniel; Kipfer, Rolf; Linke, Peter

    2010-01-01

    The concentration and carbon isotope values of dissolved methane were measured in the water column at Rock Garden, Omakere Ridge and Wairarapa areas in the first dedicated cold seep investigation along the Hikurangi Margin of New Zealand. These measurements provide a high resolution impression of the methane distribution in the water column and show that these seep sites are actively venting methane with varying intensity. The highest concentrations (up to 3500 nM) measured in water samples o...

  20. Correlation of Self Potential and Ground Magnetic Survey Techniques to Investigate Fluid Seepage in Archaeological site, Sungai Batu, Lembah Bujang, Kedah, Malaysia

    Directory of Open Access Journals (Sweden)

    Tajudeen O. Adeeko

    2018-05-01

    Full Text Available One of the substantial of geophysics is to investigate the subsurface condition of the earth (groundwater using appropriate geophysical techniques. In this research the correlation of self potential (SP and ground magnetic methods was used to investigate fluid seepage in Archaeological site, Sungai Batu, Lembah Bujang, Kedah, Malaysia. Self-potential method was used to determine flow of water, and Ground magnetic method was used to find object that can influence the result of self potential measurement and the aquifer depth, the lines were spread 0m ≤ x ≤ 9m, 0m ≤ y ≤ 30m with a trace intervals of 1.5m and 0.75m per electrode spacing respectively. The result display by Self Potential signals gives a clear understand that water flow from higher value (central towards the lower value which is mostly at the southwest part than other areas and distinct level of feasible flow at different part ranges from -30mV to +35mV,which are very related to seepage flow patterns, negative SP anomalies were related with subsurface seepage flow paths (recharge zone and positive SP anomalies were related with areas of seepage outflow (discharge zone; and Ground Magnetic signals shows good details of the buried materials with high magnetic values which was interpreted as baked clay bricks and low magnetic values indicate groundwater seepage with depth of 5m. Therefore, the two results have correlation significant at 0.8 which show good correlation in groundwater investigation in this study, which validates the results.

  1. Correlation of Self Potential and Ground Magnetic Survey Techniques to Investigate Fluid Seepage in Archaeological site, Sungai Batu, Lembah Bujang, Kedah, Malaysia

    OpenAIRE

    Tajudeen O. Adeeko; Nordiana M. Muztaza; Taqiuddin M. Zakaria; Nurina Ismail

    2018-01-01

    One of the substantial of geophysics is to investigate the subsurface condition of the earth (groundwater) using appropriate geophysical techniques. In this research the correlation of self potential (SP) and ground magnetic methods was used to investigate fluid seepage in Archaeological site, Sungai Batu, Lembah Bujang, Kedah, Malaysia. Self-potential method was used to determine flow of water, and Ground magnetic method was used to find object that can influence the result of self potential...

  2. Evaluation Of The Physical Stability, Ground Water Seepage Control, And Faunal Changes Associated With An AquaBlok® Sediment Cap

    Science.gov (United States)

    Active sediment caps are being considered for addressing contaminated sediment areas in surface-water bodies. A demonstration of an active cap designed to reduce advective transport of contaminants using AquaBlok® (active cap material) was initiated in a small study a...

  3. SEEPAGE MODEL FOR PA INCLUDING DRIFT COLLAPSE

    International Nuclear Information System (INIS)

    C. Tsang

    2004-01-01

    The purpose of this report is to document the predictions and analyses performed using the seepage model for performance assessment (SMPA) for both the Topopah Spring middle nonlithophysal (Tptpmn) and lower lithophysal (Tptpll) lithostratigraphic units at Yucca Mountain, Nevada. Look-up tables of seepage flow rates into a drift (and their uncertainty) are generated by performing numerical simulations with the seepage model for many combinations of the three most important seepage-relevant parameters: the fracture permeability, the capillary-strength parameter 1/a, and the percolation flux. The percolation flux values chosen take into account flow focusing effects, which are evaluated based on a flow-focusing model. Moreover, multiple realizations of the underlying stochastic permeability field are conducted. Selected sensitivity studies are performed, including the effects of an alternative drift geometry representing a partially collapsed drift from an independent drift-degradation analysis (BSC 2004 [DIRS 166107]). The intended purpose of the seepage model is to provide results of drift-scale seepage rates under a series of parameters and scenarios in support of the Total System Performance Assessment for License Application (TSPA-LA). The SMPA is intended for the evaluation of drift-scale seepage rates under the full range of parameter values for three parameters found to be key (fracture permeability, the van Genuchten 1/a parameter, and percolation flux) and drift degradation shape scenarios in support of the TSPA-LA during the period of compliance for postclosure performance [Technical Work Plan for: Performance Assessment Unsaturated Zone (BSC 2002 [DIRS 160819], Section I-4-2-1)]. The flow-focusing model in the Topopah Spring welded (TSw) unit is intended to provide an estimate of flow focusing factors (FFFs) that (1) bridge the gap between the mountain-scale and drift-scale models, and (2) account for variability in local percolation flux due to

  4. Seepage studies through hydraulic structures and their foundations by inactive and radio tracers

    International Nuclear Information System (INIS)

    Ansari, Azher; Mahajan, N.M.; Kamble, M.D.

    1977-01-01

    In the last ten years extensive efforts have been made by the Central Water and Power Research Station, Pune to study seepage by means of inactive and radiotracers. Various inactive tracers like electrolytes and organic dyes and radiotracers like 82 Br and 3 H in the form of tritiated water have been used for location of source of seepage. Different techniques like borehole dilution, in situ detection at various observation points and analysis of water samples in liquid scintillation spectrometer in the laboratory have been employed to suit the field conditions. Some typical studies at river valley projects indicating the techniques are enumerated. (author)

  5. Percolation testing at the F- and H-Area Seepage Basins

    International Nuclear Information System (INIS)

    McHood, M.D.

    1993-01-01

    The design of the F- and H-Area Seepage Basin contaminated groundwater remediation system requires information from multiple well pump tests (Reference 1). Soil percolation rates are needed in order to support the multiple well pump test planning. The objective of this task was to determine characteristic percolation rates for soils in four select areas where infiltration galleries are proposed. These infiltration galleries will be temporary installations built on the ground surface and used to disposes of water from the multiple well pump tests. A procedure defining the specific work process for collecting percolation rate data is contained in Appendix 3. Results from these percolation tests will be used in the design of infiltration galleries for the disposal of well water extracted during the multiple well pump tests

  6. Effect of fluid–solid coupling on shale mechanics and seepage laws

    Directory of Open Access Journals (Sweden)

    Fuquan Song

    2018-02-01

    Full Text Available In this paper, the cores of outcropped black shale of Lower Silurian Longmaxi Fm in the Yibin area, Sichuan Basin, were taken as samples to investigate the effects of extraneous water on shale mechanics and seepage laws during the production of shale gas reservoirs. Firstly, the development of fractures in water saturated cores was observed by using a VHX-5000 optical superdepth microscope. Secondly, water, formation water and slick water, as well as the damage form and compression strength of water saturated/unsaturated cores were investigated by means of a uniaxial compression testing machine and a strain testing & analysis system. Finally, the effects of fluid–solid coupling on shale gas flowing performance in different water saturations were analyzed by using a DYQ-1 multi-function displacement device. Analysis on core components shows that the Longmaxi shale is a highly crushable reservoir with a high content of fragile minerals, so fracturing stimulation is suitable for it. Shale compression strength test reveals that the effects of deionized water, formation water and slick water on shale are different, so the compression strength of shale before being saturated is quite different from that after being saturated. Due to the existence of water, the compression strength of shale drops, so the shale can be fractured easily, more fractures are generated and thus its seepage capacity is improved. Experiments on shale gas seepage under different water saturations show that under the condition of fluid–solid coupling, the higher the water saturation is, the better the propagation and seepage capacity of micro-fractures in shale under the effect of pressure. To sum up, the existence of water is beneficial to fracturing stimulation of shale gas reservoirs and helps to achieve the goal of production improvement. Keywords: Shale gas, Core, Fluid–solid coupling, Water, Compression strength, Permeability, Seepage characteristic, Sichuan Basin

  7. Results of a seepage investigation at Bear Creek Valley, Oak Ridge, Tennessee, January through September 1994

    International Nuclear Information System (INIS)

    Robinson, J.A.; Johnson, G.C.

    1996-01-01

    A seepage investigation was conducted of 4,600 acres of Bear Creek Valley southwest of the Y-12 Plant, Oak Ridge, Tennessee, for the period of January through September 1994. The data was collected to help the Y-12 Environmental Restoration Program develop a better understanding of ground-water and surface-water interactions, recharge and discharge relations, and ground-water flow patterns. The project was divided into three phases: a reconnaissance and mapping of seeps, springs, and stream-measurement sites; a high base flow seepage investigation; and a low base flow seepage investigation. This report describes the results of the investigation. It includes a map showing measurement site locations and tables that list the coordinates for each site and measurements of discharge, pH, specific conductance, temperature, and dissolved oxygen

  8. BOTTOM DEPOSITS OF STRATIFIED, SEEPAGE, URBAN LAKE (ON EXAMPLE OF TYRSKO LAKE, POLAND AS A FACTOR POTENTIALLY SHAPING LAKE WATER QUALITY

    Directory of Open Access Journals (Sweden)

    Renata Augustyniak

    2017-09-01

    The obtained results revealed, that bottom sediment of Tyrsko Lake can be classified as mixed, silica-organic type, with quite high content of iron (over 4% Fe in d.w.. The total phosphorus content was ca. 3.5 mg P g-1 d.w. on average. Phosphorus in bottom sediment was bound mainly with organic matter (NaOH-nrP fraction, which had over 50% share in TP. Easy mobile fractions (NH4-Cl-P and BD-P together included ca 5% to 7 % TP only. The obtained results show, that bottom sediment of Tyrsko Lake can bind phosphorus quite effectively. Calculated internal mineral phosphorus loading during summer stagnation period was 10.9 kg P and it was lower that the assessed annual external phosphorus load (22.6 kg P y-1. The assessed annual phosphorus loading from both sources still was lower than critical load according to Vollenweider criteria. But due to the fact that internal loading phenomenon is occurring in the lake it should be taken into consideration that the lake water quality can deteriorate gradually during the longer time perspective. These findings should be taken into consideration in the future if the potential protection and restoration procedures will be developed.

  9. A tube seepage meter for in situ measurement of seepage rate and groundwater sampling

    Science.gov (United States)

    Solder, John; Gilmore, Troy E.; Genereux, David P.; Solomon, D. Kip

    2016-01-01

    We designed and evaluated a “tube seepage meter” for point measurements of vertical seepage rates (q), collecting groundwater samples, and estimating vertical hydraulic conductivity (K) in streambeds. Laboratory testing in artificial streambeds show that seepage rates from the tube seepage meter agreed well with expected values. Results of field testing of the tube seepage meter in a sandy-bottom stream with a mean seepage rate of about 0.5 m/day agreed well with Darcian estimates (vertical hydraulic conductivity times head gradient) when averaged over multiple measurements. The uncertainties in q and K were evaluated with a Monte Carlo method and are typically 20% and 60%, respectively, for field data, and depend on the magnitude of the hydraulic gradient and the uncertainty in head measurements. The primary advantages of the tube seepage meter are its small footprint, concurrent and colocated assessments of q and K, and that it can also be configured as a self-purging groundwater-sampling device.

  10. Numerical Analysis on Seepage in the deep overburden CFRD

    Science.gov (United States)

    Zeyu, GUO; Junrui, CHAI; Yuan, QIN

    2017-12-01

    There are many problems in the construction of hydraulic structures on deep overburden because of its complex foundation structure and poor geological condition. Seepage failure is one of the main problems. The Combination of the seepage control system of the face rockfill dam and the deep overburden can effectively control the seepage of construction of the concrete face rockfill dam on the deep overburden. Widely used anti-seepage measures are horizontal blanket, waterproof wall, curtain grouting and so on, but the method, technique and its effect of seepage control still have many problems thus need further study. Due to the above considerations, Three-dimensional seepage field numerical analysis based on practical engineering case is conducted to study the seepage prevention effect under different seepage prevention methods, which is of great significance to the development of dam technology and the development of hydropower resources in China.

  11. Seepage into drifts in unsaturated fractured rock at Yucca Mountain

    International Nuclear Information System (INIS)

    Birkholzer, Jens; Li, Guomin; Tsang, Chin-Fu; Tsang, Yvonne

    1998-01-01

    An important issue for the long-term performance of underground nuclear waste repository is the rate of seepage into the waste emplacement drifts. A prediction of the future seepage rate is particularly complicated for the potential repository site at Yucca Mountain, Nevada, as it is located in thick, partially saturated, fractured tuff formations. The long-term situation in the drifts several thousand years after waste emplacement will be characterized by a relative humidity level close to or equal to 100%, as the drifts will be sealed and unventilated, and the waste packages will have cooled. The underground tunnels will then act as capillary barriers for the unsaturated flow, ideally diverting water around them, if the capillary forces are stronger than gravity and viscous forces. Seepage into the drifts will only be possible if the hydraulic pressure in the rock close to the drift walls increases to positive values; i.e., the flow field becomes locally saturated. In the present work, they have developed and applied a methodology to study the potential rate of seepage into underground cavities embedded in a variably saturated, heterogeneous fractured rock formation. The fractured rock mass is represented as a stochastic continuum where the fracture permeabilities vary by several orders of magnitude. Three different realizations of random fracture permeability fields are generated, with the random permeability structure based on extensive fracture mapping, borehole video analysis, and in-situ air permeability testing. A 3-D numerical model is used to simulate the heterogeneous steady-state flow field around the drift, with the drift geometry explicitly represented within the numerical discretization grid. A variety of flow scenarios are considered assuming present-day and future climate conditions at Yucca Mountain. The numerical study is complemented by theoretical evaluations of the drift seepage problem, using stochastic perturbation theory to develop a better

  12. DRIFT-SCALE COUPLED PROCESSES (DST AND TH SEEPAGE) MODELS

    International Nuclear Information System (INIS)

    J.T. Birkholzer; S. Mukhopadhyay

    2005-01-01

    The purpose of this report is to document drift-scale modeling work performed to evaluate the thermal-hydrological (TH) behavior in Yucca Mountain fractured rock close to waste emplacement drifts. The heat generated by the decay of radioactive waste results in rock temperatures elevated from ambient for thousands of years after emplacement. Depending on the thermal load, these temperatures are high enough to cause boiling conditions in the rock, giving rise to water redistribution and altered flow paths. The predictive simulations described in this report are intended to investigate fluid flow in the vicinity of an emplacement drift for a range of thermal loads. Understanding the TH coupled processes is important for the performance of the repository because the thermally driven water saturation changes affect the potential seepage of water into waste emplacement drifts. Seepage of water is important because if enough water gets into the emplacement drifts and comes into contact with any exposed radionuclides, it may then be possible for the radionuclides to be transported out of the drifts and to the groundwater below the drifts. For above-boiling rock temperatures, vaporization of percolating water in the fractured rock overlying the repository can provide an important barrier capability that greatly reduces (and possibly eliminates) the potential of water seeping into the emplacement drifts. In addition to this thermal process, water is inhibited from entering the drift opening by capillary forces, which occur under both ambient and thermal conditions (capillary barrier). The combined barrier capability of vaporization processes and capillary forces in the near-field rock during the thermal period of the repository is analyzed and discussed in this report

  13. Numerical experiments on the probability of seepage into underground openings in heterogeneous fractured rock

    International Nuclear Information System (INIS)

    Birkholzer, J.; Li, G.; Tsang, C.F.; Tsang, Y.

    1998-01-01

    An important issue for the performance of underground nuclear waste repositories is the rate of seepage into the waste emplacement drifts. A prediction of this rate is particularly complicated for the potential repository site at Yucca Mountain, Nevada, because it is located in thick, unsaturated, fractured tuff formations. Underground opening in unsaturated media might act as capillary barriers, diverting water around them. In the present work, they study the potential rate of seepage into drifts as a function of the percolation flux at Yucca Mountain, based on a stochastic model of the fractured rock mass in the drift vicinity. A variety of flow scenarios are considered, assuming present-day and possible future climate conditions. They show that the heterogeneity in the flow domain is a key factor controlling seepage rates, since it causes channelized flow and local ponding in the unsaturated flow field

  14. Radon determination in ground water

    Energy Technology Data Exchange (ETDEWEB)

    Segovia A, N.; Bulbulian G, S

    1991-08-15

    Studies on natural radioactivity in ground water were started in Mexico in San Luis Potosi state followed by samplings from deep wells and springs in the states of Mexico and Michoacan. The samples were analyzed for solubilized and {sup 226} Ra- supported {sup 222} Rn. Some of them were also studied for {sup 234} U/ {sup 238} U activity ratio. In this paper we discuss the activities obtained and their relationship with the geologic characteristics of the studied zones. (Author)

  15. Radon determination in ground water

    International Nuclear Information System (INIS)

    Segovia A, N.; Bulbulian G, S.

    1991-08-01

    Studies on natural radioactivity in ground water were started in Mexico in San Luis Potosi state followed by samplings from deep wells and springs in the states of Mexico and Michoacan. The samples were analyzed for solubilized and 226 Ra- supported 222 Rn. Some of them were also studied for 234 U/ 238 U activity ratio. In this paper we discuss the activities obtained and their relationship with the geologic characteristics of the studied zones. (Author)

  16. Natural convection in tunnels at Yucca Mountain and impact on drift seepage

    Energy Technology Data Exchange (ETDEWEB)

    Halecky, N.; Birkholzer, J.T.; Peterson, P.

    2010-04-15

    The decay heat from radioactive waste that is to be disposed in the once proposed geologic repository at Yucca Mountain (YM) will significantly influence the moisture conditions in the fractured rock near emplacement tunnels (drifts). Additionally, large-scale convective cells will form in the open-air drifts and will serve as an important mechanism for the transport of vaporized pore water from the fractured rock in the drift center to the drift end. Such convective processes would also impact drift seepage, as evaporation could reduce the build up of liquid water at the tunnel wall. Characterizing and understanding these liquid water and vapor transport processes is critical for evaluating the performance of the repository, in terms of water-induced canister corrosion and subsequent radionuclide containment. To study such processes, we previously developed and applied an enhanced version of TOUGH2 that solves for natural convection in the drift. We then used the results from this previous study as a time-dependent boundary condition in a high-resolution seepage model, allowing for a computationally efficient means for simulating these processes. The results from the seepage model show that cases with strong natural convection effects are expected to improve the performance of the repository, since smaller relative humidity values, with reduced local seepage, form a more desirable waste package environment.

  17. On leakage and seepage from geological carbon sequestration sites

    Energy Technology Data Exchange (ETDEWEB)

    Oldenburg, C.M.; Unger, A.J.A.; Hepple, R.P.; Jordan, P.D.

    2002-07-18

    Geologic carbon sequestration is one strategy for reducing the rate of increase of global atmospheric carbon dioxide (CO{sub 2} ) concentrations (IEA, 1997; Reichle, 2000). As used here, the term geologic carbon sequestration refers to the direct injection of supercritical CO{sub 2} deep into subsurface target formations. These target formations will typically be either depleted oil and gas reservoirs, or brine-filled permeable formations referred to here as brine formations. Injected CO{sub 2} will tend to be trapped by one or more of the following mechanisms: (1) permeability trapping, for example when buoyant supercritical CO{sub 2} rises until trapped by a confining caprock; (2) solubility trapping, for example when CO{sub 2} dissolves into the aqueous phase in water-saturated formations, or (3) mineralogic trapping, such as occurs when CO{sub 2} reacts to produce stable carbonate minerals. When CO{sub 2} is trapped in the subsurface by any of these mechanisms, it is effectively sequestered away from the atmosphere where it would otherwise act as a greenhouse gas. The purpose of this report is to summarize our work aimed at quantifying potential CO{sub 2} seepage due to leakage from geologic carbon sequestration sites. The approach we take is to present first the relevant properties of CO{sub 2} over the range of conditions from the deep subsurface to the vadose zone (Section 2), and then discuss conceptual models for how leakage might occur (Section 3). The discussion includes consideration of gas reservoir and natural gas storage analogs, along with some simple estimates of seepage based on assumed leakage rates. The conceptual model discussion provides the background for the modeling approach wherein we focus on simulating transport in the vadose zone, the last potential barrier to CO{sub 2} seepage (Section 4). Because of the potentially wide range of possible properties of actual future geologic sequestration sites, we carry out sensitivity analyses by

  18. A calorimetric method to determine water activity.

    Science.gov (United States)

    Björklund, Sebastian; Wadsö, Lars

    2011-11-01

    A calorimetric method to determine water activity covering the full range of the water activity scale is presented. A dry stream of nitrogen gas is passed either over the solution whose activity should be determined or left dry before it is saturated by bubbling through water in an isothermal calorimeter. The unknown activity is in principle determined by comparing the thermal power of vaporization related to the gas stream with unknown activity to that with zero activity. Except for three minor corrections (for pressure drop, non-perfect humidification, and evaporative cooling) the unknown water activity is calculated solely based on the water activity end-points zero and unity. Thus, there is no need for calibration with references with known water activities. The method has been evaluated at 30 °C by measuring the water activity of seven aqueous sodium chloride solutions ranging from 0.1 mol kg(-1) to 3 mol kg(-1) and seven saturated aqueous salt solutions (LiCl, MgCl(2), NaBr, NaCl, KCl, KNO(3), and K(2)SO(4)) with known water activities. The performance of the method was adequate over the complete water activity scale. At high water activities the performance was excellent, which is encouraging as many other methods used for water activity determination have limited performance at high water activities. © 2011 American Institute of Physics

  19. Geochemical Modeling Of F Area Seepage Basin Composition And Variability

    International Nuclear Information System (INIS)

    Millings, M.; Denham, M.; Looney, B.

    2012-01-01

    From the 1950s through 1989, the F Area Seepage Basins at the Savannah River Site (SRS) received low level radioactive wastes resulting from processing nuclear materials. Discharges of process wastes to the F Area Seepage Basins followed by subsequent mixing processes within the basins and eventual infiltration into the subsurface resulted in contamination of the underlying vadose zone and downgradient groundwater. For simulating contaminant behavior and subsurface transport, a quantitative understanding of the interrelated discharge-mixing-infiltration system along with the resulting chemistry of fluids entering the subsurface is needed. An example of this need emerged as the F Area Seepage Basins was selected as a key case study demonstration site for the Advanced Simulation Capability for Environmental Management (ASCEM) Program. This modeling evaluation explored the importance of the wide variability in bulk wastewater chemistry as it propagated through the basins. The results are intended to generally improve and refine the conceptualization of infiltration of chemical wastes from seepage basins receiving variable waste streams and to specifically support the ASCEM case study model for the F Area Seepage Basins. Specific goals of this work included: (1) develop a technically-based 'charge-balanced' nominal source term chemistry for water infiltrating into the subsurface during basin operations, (2) estimate the nature of short term and long term variability in infiltrating water to support scenario development for uncertainty quantification (i.e., UQ analysis), (3) identify key geochemical factors that control overall basin water chemistry and the projected variability/stability, and (4) link wastewater chemistry to the subsurface based on monitoring well data. Results from this study provide data and understanding that can be used in further modeling efforts of the F Area groundwater plume. As identified in this study, key geochemical factors affecting basin

  20. Vertical migration of fine-grained sediments from interior to surface of seabed driven by seepage flows-`sub-bottom sediment pump action'

    Science.gov (United States)

    Zhang, Shaotong; Jia, Yonggang; Wen, Mingzheng; Wang, Zhenhao; Zhang, Yaqi; Zhu, Chaoqi; Li, Bowen; Liu, Xiaolei

    2017-02-01

    A scientific hypothesis is proposed and preliminarily verified in this paper: under the driving of seepage flows, there might be a vertical migration of fine-grained soil particles from interior to surface of seabed, which is defined as `sub-bottom sediment pump action' in this paper. Field experiments were performed twice on the intertidal flat of the Yellow River delta to study this process via both trapping the pumped materials and recording the pore pressures in the substrate. Experimental results are quite interesting as we did observe yellow slurry which is mainly composed of fine-grained soil particles appearing on the seabed surface; seepage gradients were also detected in the intertidal flat, under the action of tides and small wind waves. Preliminary conclusions are that `sediment pump' occurs when seepage force exceeds a certain threshold: firstly, it is big enough to disconnect the soil particles from the soil skeleton; secondly, the degree of seabed fluidization or bioturbation is big enough to provide preferred paths for the detached materials to migrate upwards. Then they would be firstly pumped from interior to the surface of seabed and then easily re-suspended into overlying water column. Influential factors of `sediment pump' are determined as hydrodynamics (wave energy), degree of consolidation, index of bioturbation (permeability) and content of fine-grained materials (sedimentary age). This new perspective of `sediment pump' may provide some implications for the mechanism interpretation of several unclear geological phenomena in the Yellow River delta area.

  1. Radioactive Seepage through Groundwater Flow from the Uranium Mines, Namibia

    Directory of Open Access Journals (Sweden)

    Tamiru Abiye

    2017-02-01

    Full Text Available The study focused on the seepage of uranium from unlined tailing dams into the alluvial aquifer in the Gawib River floodplain in Namibia where the region solely relies on groundwater for its economic activities as a result of arid climatic condition. The study reviewed previous works besides water sample collection and analyses for major ions, metals and environmental isotopes in addition to field tests on physico-chemical parameters (pH, Electrical Conductivity, Redox and T. Estimation of seepage velocity (true velocity of groundwater flow has been conducted in order to understand the extent of radioactive plume transport. The hydrochemistry, stable isotopes and tritium results show that there is uranium contamination from the unlined uranium tailings in the Gawib shallow aquifer system which suggests high permeability of the alluvial aquifer facilitating groundwater flow in the arid region. The radioactive contaminants could spread into the deeper aquifer system through the major structures such as joints and faults. The contamination plume could also spread downstream into the Swakop River unless serious interventions are employed. There is also a very high risk of the plume to reach the Atlantic Ocean through seasonal flash floods that occurs in the area.

  2. H-Area Seepage Basin (H-HWMF): Fourth quarterly 1989, groundwater quality assessment report

    Energy Technology Data Exchange (ETDEWEB)

    1990-03-01

    During the fourth quarter of 1989 the wells which make up the H-Area Seepage Basins (H-HWMF){sup 1} monitoring network were sampled. Laboratory analyses were performed to measure levels of hazardous constituents, indicator parameters, tritium, and gross alpha. A Gas Chromatograph Mass Spectrometer (GCMS) scan was performed on all wells sampled to determine any hazardous organic constituents present in the groundwater. The primary contaminants observed at wells monitoring the H-Area Seepage Basins are tritium, nitrate, mercury, gross alpha, and total radium.

  3. Microbial community changes along the active seepage site of one cold seep in the Red Sea.

    KAUST Repository

    Cao, Huiluo

    2015-07-21

    The active seepage of the marine cold seeps could be a critical process for the exchange of energy between the submerged geosphere and the sea floor environment through organic-rich fluids, potentially even affecting surrounding microbial habitats. However, few studies have investigated the associated microbial community changes. In the present study, 16S rRNA genes were pyrosequenced to decipher changes in the microbial communities from the Thuwal seepage point in the Red Sea to nearby marine sediments in the brine pool, normal marine sediments and water, and benthic microbial mats. An unexpected number of reads from unclassified groups were detected in these habitats; however, the ecological functions of these groups remain unresolved. Furthermore, ammonia-oxidizing archaeal community structures were investigated using the ammonia monooxygenase subunit A (amoA) gene. Analysis of amoA showed that planktonic marine habitats, including seeps and marine water, hosted archaeal ammonia oxidizers that differed from those in microbial mats and marine sediments, suggesting modifications of the ammonia oxidizing archaeal (AOA) communities along the environmental gradient from active seepage sites to peripheral areas. Changes in the microbial community structure of AOA in different habitats (water vs. sediment) potentially correlated with changes in salinity and oxygen concentrations. Overall, the present results revealed for the first time unanticipated novel microbial groups and changes in the ammonia-oxidizing archaea in response to environmental gradients near the active seepages of a cold seep.

  4. Microbial community changes along the active seepage site of one cold seep in the Red Sea.

    KAUST Repository

    Cao, Huiluo; Zhang, Weipeng; Wang, Yong; Qian, Pei-Yuan

    2015-01-01

    The active seepage of the marine cold seeps could be a critical process for the exchange of energy between the submerged geosphere and the sea floor environment through organic-rich fluids, potentially even affecting surrounding microbial habitats. However, few studies have investigated the associated microbial community changes. In the present study, 16S rRNA genes were pyrosequenced to decipher changes in the microbial communities from the Thuwal seepage point in the Red Sea to nearby marine sediments in the brine pool, normal marine sediments and water, and benthic microbial mats. An unexpected number of reads from unclassified groups were detected in these habitats; however, the ecological functions of these groups remain unresolved. Furthermore, ammonia-oxidizing archaeal community structures were investigated using the ammonia monooxygenase subunit A (amoA) gene. Analysis of amoA showed that planktonic marine habitats, including seeps and marine water, hosted archaeal ammonia oxidizers that differed from those in microbial mats and marine sediments, suggesting modifications of the ammonia oxidizing archaeal (AOA) communities along the environmental gradient from active seepage sites to peripheral areas. Changes in the microbial community structure of AOA in different habitats (water vs. sediment) potentially correlated with changes in salinity and oxygen concentrations. Overall, the present results revealed for the first time unanticipated novel microbial groups and changes in the ammonia-oxidizing archaea in response to environmental gradients near the active seepages of a cold seep.

  5. Fluorimetric determination of uranium in water

    International Nuclear Information System (INIS)

    Acosta L, E.

    1992-02-01

    The fluorimetric method for the determination of microquantities of uranium in water is described. This method covers the determination of uranium in water in the interval from 0.2 to 50 ppm on 50 ml. of radioactive base sample. These limits can be variable if the volume of the aliquot one of the base sample is changed, as well as the volume of the used aliquot one for to the final determination of uranium. (Author)

  6. Seepage investigation by using Isotope and Geophysical Techniques in Gumti Flood Embankment/Dyke, Comilla

    International Nuclear Information System (INIS)

    Ahmed, N.; Wallin, B. G.; Majumder, R. K.; Mikail, M.; Rahman, M. S.

    2004-06-01

    Gumti Flood Control Embankment/Dyke is vital for irrigation water supply and flood control. Water seepage/leakage and slope failures are the major issues in Gumti earthen dyke. The distinct seepage and slope failure zone were observed at three places (Farizpur, Kathalia and Ebdarpur) along the countryside of left dyke. The isotopic technique has been integrated in the conventional hydrologic investigations. The isotope methodology works essentially by developing a characteristics pattern of the isotopic composition to identify the sources and flow dynamics of seeping/leaking in the dykes. Two sampling campaigns were conducted; one was on October, 2002 and the other was on July, 2003; near the seepage/leakage site for chemical analysis and stable isotopic analysis (''2H and ''1 8 O). Both samplings were done after recession of peak water level in the Gumti river. Interpretation of the hydrochemical data implies that the groundwater near the investigated seepage zones is Na-Ca-HCO 3 type and the river water is Ca-Mg-HCO 3 type. The chlorides content of both groundwater and river water are found mostly similar, indicating mixing between the two water system. The stable isotopes (''2H and ''1 8 O) of groundwater fall on the Meteoric Water Line, ranging the oxygen-18 values from -4.98 to -5.46 per mil and deuterium values from -30.0 to -33.6 per mil. It indicates the recharge from the river water during peak water level in the river Gumti. On the other hand, the stable isotopes of the Gumti river show some evaporation effect, which might have occurred due to stagnation of flowing water in the river. The oxygen-18 and deuterium values for river water range from -3.61 to -4.43 per mil and from -22.30 to -28.48 per mil respectively. These isotope results reflect the hydraulic connectivity between the river water and groundwater through the base of dyke. The earth imaging resistivity survey was carried out in the dry period along the four above mentioned areas of the Gumti

  7. A steady state solution for ditch drainage problem with special reference to seepage face and unsaturated zone flow contribution: Derivation of a new drainage spacing eqaution

    Science.gov (United States)

    Yousfi, Ammar; Mechergui, Mohammed

    2016-04-01

    al. (2001). In this work, a novel solution based on theoretical approach will be adapted to incorporate both the seepage face and the unsaturated zone flow contribution for solving ditch drained aquifers problems. This problem will be tackled on the basis of the approximate 2D solution given by Castro-Orgaz et al. (2012). This given solution yields the generalized water table profile function with a suitable boundary condition to be determined and provides a modified DF theory which permits as an outcome the analytical determination of the seepage face. To assess the ability of the developed equation for water-table estimations, the obtained results were compared with numerical solutions to the 2-D problem under different conditions. It is shown that results are in fair agreement and thus the resulting model can be used for designing ditch drainage systems. With respect to drainage design, the spacings calculated with the newly derived equation are compared with those computed from the DF theory. It is shown that the effect of the unsaturated zone flow contribution is limited to sandy soils and The calculated maximum increase in drain spacing is about 30%. Keywords: subsurface ditch drainage; unsaturated zone; seepage face; water-table, ditch spacing equation

  8. Assessment of linear anionic polyacrylamide application to irrigation canals for seepage control

    Directory of Open Access Journals (Sweden)

    Hamil Uribe

    2013-09-01

    Full Text Available South- central area of Chile area has a Mediterranean climate and high crop water requirements. Irrigation water is distributed through long channels which have low water conveyance efficiency (Ec, difficult to improve by conventional techniques. The objective of this study was to quantify Ec and to evaluate the use of Linear Anionic Polyacrylamide (LA-PAM to reduce seepage losses. The study was carried out in south-central area of Chile, (UTM Coordinate N 5745000; E 725000 m, datum is WGS-84, zone 18S in 250 km of channels whose flow varied between 0.12 and 24.6 m3 s–1. Water users indicated channel reaches with potential low Ec, which were selected for LA-PAM application. In 11 reaches between 0.51 and 3 km in length, 1 to 3 LAPAM applications were performed at rates of 10 kg ha–1, considering the wet perimeter area as basis of calculation. Thirty-one LA-PAM applications were performed over a 30.5 km length. Most of the channels were large enough to allow motorboat moving against the current to carry-out LA-PAM application. Water flow was measured (StreamPro ADCP at both ends of selected reaches before and after granular LAPAM application. Weekly measurements were made to quantify treatment effect duration. Water turbidity and temperature were measured. Channels showed variable Ec from 87% to 94%. Two reaches showed 6% water gains. In more than 80% cases LA-PAM effect was positive, achieving loss reductions of 15 to 760 L s–1. In other cases LA-PAM had a negative effect since it mainly affected water entry into the channel. It was determined that field conditions referred by users as indicators of Ec are not always correct and vary in time according to climatic conditions. Ec was estimated and it was possible to reduce seepage through LA-PAM applications. This allow increasing irrigation security in critical periods, especially under drought conditions.

  9. Groundwater flow and heterogeneous discharge into a seepage lake

    DEFF Research Database (Denmark)

    Kazmierczak, Jolanta; Müller, Sascha; Nilsson, B.

    2016-01-01

    with the lake remained under seemingly steady state conditions across seasons, a high spatial and temporal heterogeneity in the discharge to the lake was observed. The results showed that part of the groundwater flowing from the west passes beneath the lake and discharges at the eastern shore, where groundwater......Groundwater discharge into a seepage lake was investigated by combining flux measurements, hydrochemical tracers, geological information, and a telescopic modeling approach using first two-dimensional (2-D) regional then 2-D local flow and flow path models. Discharge measurements and hydrochemical...... tracers supplement each other. Discharge measurements yield flux estimates but rarely provide information about the origin and flow path of the water. Hydrochemical tracers may reveal the origin and flow path of the water but rarely provide any information about the flux. While aquifer interacting...

  10. Steady flow rate to a partially penetrating well with seepage face in an unconfined aquifer

    Science.gov (United States)

    Behrooz-Koohenjani, Siavash; Samani, Nozar; Kompani-Zare, Mazda

    2011-06-01

    The flow rate to fully screened, partially penetrating wells in an unconfined aquifer is numerically simulated using MODFLOW 2000, taking into account the flow from the seepage face and decrease in saturated thickness of the aquifer towards the well. A simple three-step method is developed to find the top of the seepage face and hence the seepage-face length. The method is verified by comparing it with the results of previous predictive methods. The results show that the component of flow through the seepage face can supply a major portion of the total pumping rate. Variations in flow rate as a function of the penetration degree, elevation of the water level in the well and the distance to the far constant head boundary are investigated and expressed in terms of dimensionless curves and equations. These curves and equations can be used to design the degree of penetration for which the allowable steady pumping rate is attained for a given elevation of water level in the well. The designed degree of penetration or flow rate will assure the sustainability of the aquifer storage, and can be used as a management criterion for issuing drilling well permits by groundwater protection authorities.

  11. Evaluation of seepage and discharge uncertainty in the middle Snake River, southwestern Idaho

    Science.gov (United States)

    Wood, Molly S.; Williams, Marshall L.; Evetts, David M.; Vidmar, Peter J.

    2014-01-01

    The U.S. Geological Survey, in cooperation with the State of Idaho, Idaho Power Company, and the Idaho Department of Water Resources, evaluated seasonal seepage gains and losses in selected reaches of the middle Snake River, Idaho, during November 2012 and July 2013, and uncertainty in measured and computed discharge at four Idaho Power Company streamgages. Results from this investigation will be used by resource managers in developing a protocol to calculate and report Adjusted Average Daily Flow at the Idaho Power Company streamgage on the Snake River below Swan Falls Dam, near Murphy, Idaho, which is the measurement point for distributing water to owners of hydropower and minimum flow water rights in the middle Snake River. The evaluated reaches of the Snake River were from King Hill to Murphy, Idaho, for the seepage studies and downstream of Lower Salmon Falls Dam to Murphy, Idaho, for evaluations of discharge uncertainty. Computed seepage was greater than cumulative measurement uncertainty for subreaches along the middle Snake River during November 2012, the non-irrigation season, but not during July 2013, the irrigation season. During the November 2012 seepage study, the subreach between King Hill and C J Strike Dam had a meaningful (greater than cumulative measurement uncertainty) seepage gain of 415 cubic feet per second (ft3/s), and the subreach between Loveridge Bridge and C J Strike Dam had a meaningful seepage gain of 217 ft3/s. The meaningful seepage gain measured in the November 2012 seepage study was expected on the basis of several small seeps and springs present along the subreach, regional groundwater table contour maps, and results of regional groundwater flow model simulations. Computed seepage along the subreach from C J Strike Dam to Murphy was less than cumulative measurement uncertainty during November 2012 and July 2013; therefore, seepage cannot be quantified with certainty along this subreach. For the uncertainty evaluation, average

  12. Sr90 determination in calcareous water

    International Nuclear Information System (INIS)

    Cohen, P.; Pardo, G.; Wormser, G.

    1958-01-01

    The Straub method (ref. 2) for determination of radioactive strontium in water containing calcium is valid within very wide limits, and particularly in the case of residual water from the chemical purification treatment of the radioactive liquid effluent at the C.E.N. Saclay. (author) [fr

  13. Calorimetric determination of the water energy dosis

    International Nuclear Information System (INIS)

    Krauss, Achim

    2013-01-01

    The water calorimeter of the PTB is described, which consists of a water phantom operated at 4 C, whereby the radiation-induced temperature raise is measured by means of thermistors. As application example the determination of the radiation-quality dependent k Q factors of ionization chambers for all medical accelerators present in the PTB is described. (HSI)

  14. Subduction zone earthquake probably triggered submarine hydrocarbon seepage offshore Pakistan

    Science.gov (United States)

    Fischer, David; José M., Mogollón; Michael, Strasser; Thomas, Pape; Gerhard, Bohrmann; Noemi, Fekete; Volkhard, Spiess; Sabine, Kasten

    2014-05-01

    Seepage of methane-dominated hydrocarbons is heterogeneous in space and time, and trigger mechanisms of episodic seep events are not well constrained. It is generally found that free hydrocarbon gas entering the local gas hydrate stability field in marine sediments is sequestered in gas hydrates. In this manner, gas hydrates can act as a buffer for carbon transport from the sediment into the ocean. However, the efficiency of gas hydrate-bearing sediments for retaining hydrocarbons may be corrupted: Hypothesized mechanisms include critical gas/fluid pressures beneath gas hydrate-bearing sediments, implying that these are susceptible to mechanical failure and subsequent gas release. Although gas hydrates often occur in seismically active regions, e.g., subduction zones, the role of earthquakes as potential triggers of hydrocarbon transport through gas hydrate-bearing sediments has hardly been explored. Based on a recent publication (Fischer et al., 2013), we present geochemical and transport/reaction-modelling data suggesting a substantial increase in upward gas flux and hydrocarbon emission into the water column following a major earthquake that occurred near the study sites in 1945. Calculating the formation time of authigenic barite enrichments identified in two sediment cores obtained from an anticlinal structure called "Nascent Ridge", we find they formed 38-91 years before sampling, which corresponds well to the time elapsed since the earthquake (62 years). Furthermore, applying a numerical model, we show that the local sulfate/methane transition zone shifted upward by several meters due to the increased methane flux and simulated sulfate profiles very closely match measured ones in a comparable time frame of 50-70 years. We thus propose a causal relation between the earthquake and the amplified gas flux and present reflection seismic data supporting our hypothesis that co-seismic ground shaking induced mechanical fracturing of gas hydrate-bearing sediments

  15. Control and prevention of seepage from uranium mill waste disposal facilities

    International Nuclear Information System (INIS)

    Williams, R.E.

    1978-01-01

    This paper constitutes an analysis of the technologies which are available for the prevention of movement of waste waters out of uranium mill waste disposal facilities via sub-surface routes. Hydrogeologic criteria for potential uranium mill waste disposal sites and mathematical modeling of contaminant migration in ground water are presented. Methods for prevention of seepage from uranium mill waste disposal facilities are investigated: liners, clay seals, synthetic polymeric membranes (PVC, polyethylene, chlorinated polyethylene, hypalon, butyl rubber, neoprene, elasticized polyolefin)

  16. A method for estimating spatially variable seepage and hydrualic conductivity in channels with very mild slopes

    Science.gov (United States)

    Shanafield, Margaret; Niswonger, Richard G.; Prudic, David E.; Pohll, Greg; Susfalk, Richard; Panday, Sorab

    2014-01-01

    Infiltration along ephemeral channels plays an important role in groundwater recharge in arid regions. A model is presented for estimating spatial variability of seepage due to streambed heterogeneity along channels based on measurements of streamflow-front velocities in initially dry channels. The diffusion-wave approximation to the Saint-Venant equations, coupled with Philip's equation for infiltration, is connected to the groundwater model MODFLOW and is calibrated by adjusting the saturated hydraulic conductivity of the channel bed. The model is applied to portions of two large water delivery canals, which serve as proxies for natural ephemeral streams. Estimated seepage rates compare well with previously published values. Possible sources of error stem from uncertainty in Manning's roughness coefficients, soil hydraulic properties and channel geometry. Model performance would be most improved through more frequent longitudinal estimates of channel geometry and thalweg elevation, and with measurements of stream stage over time to constrain wave timing and shape. This model is a potentially valuable tool for estimating spatial variability in longitudinal seepage along intermittent and ephemeral channels over a wide range of bed slopes and the influence of seepage rates on groundwater levels.

  17. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    International Nuclear Information System (INIS)

    Sonnenthale, E.

    2001-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the Near-Field Environment (NFE) and Unsaturated Zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrologic-chemical (THC) processes on unsaturated zone flow and transport. This is in accordance with the ''Technical Work Plan (TWP) for Unsaturated Zone Flow and Transport Process Model Report'', Addendum D, Attachment D-4 (Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) 2000 [1534471]) and ''Technical Work Plan for Nearfield Environment Thermal Analyses and Testing'' (CRWMS M and O 2000 [153309]). These models include the Drift Scale Test (DST) THC Model and several THC seepage models. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal loading conditions, and predict the chemistry of waters and gases entering potential waste-emplacement drifts. The intended use of this AMR is to provide input for the following: Performance Assessment (PA); Near-Field Environment (NFE) PMR; Abstraction of Drift-Scale Coupled Processes AMR (ANL-NBS-HS-000029); and UZ Flow and Transport Process Model Report (PMR). The work scope for this activity is presented in the TWPs cited above, and summarized as follows: Continue development of the repository drift-scale THC seepage model used in support of the TSPA in-drift geochemical model; incorporate heterogeneous fracture property realizations; study sensitivity of results to changes in input data and mineral assemblage; validate the DST model by comparison with field data; perform simulations to predict mineral dissolution and precipitation and their effects on fracture properties and chemistry of water (but not flow rates) that may seep into drifts; submit modeling results to the TDMS and document the models. The model development, input data, sensitivity and validation studies described in this AMR are

  18. Combined use of thermal methods and seepage meters to efficiently locate, quantify, and monitor focused groundwater discharge to a sand-bed stream

    Science.gov (United States)

    Rosenberry, Donald O.; Briggs, Martin A.; Delin, Geoffrey N.; Hare, Danielle K.

    2016-01-01

    Quantifying flow of groundwater through streambeds often is difficult due to the complexity of aquifer-scale heterogeneity combined with local-scale hyporheic exchange. We used fiber-optic distributed temperature sensing (FO-DTS), seepage meters, and vertical temperature profiling to locate, quantify, and monitor areas of focused groundwater discharge in a geomorphically simple sand-bed stream. This combined approach allowed us to rapidly focus efforts at locations where prodigious amounts of groundwater discharged to the Quashnet River on Cape Cod, Massachusetts, northeastern USA. FO-DTS detected numerous anomalously cold reaches one to several m long that persisted over two summers. Seepage meters positioned upstream, within, and downstream of 7 anomalously cold reaches indicated that rapid groundwater discharge occurred precisely where the bed was cold; median upward seepage was nearly 5 times faster than seepage measured in streambed areas not identified as cold. Vertical temperature profilers deployed next to 8 seepage meters provided diurnal-signal-based seepage estimates that compared remarkably well with seepage-meter values. Regression slope and R2 values both were near 1 for seepage ranging from 0.05 to 3.0 m d−1. Temperature-based seepage model accuracy was improved with thermal diffusivity determined locally from diurnal signals. Similar calculations provided values for streambed sediment scour and deposition at subdaily resolution. Seepage was strongly heterogeneous even along a sand-bed river that flows over a relatively uniform sand and fine-gravel aquifer. FO-DTS was an efficient method for detecting areas of rapid groundwater discharge, even in a strongly gaining river, that can then be quantified over time with inexpensive streambed thermal methods.

  19. Determination of water retention curves of concrete

    International Nuclear Information System (INIS)

    Villar, M.V.; Romero, F.J.

    2015-01-01

    The water retention curves of concrete and mortar obtained with two different techniques and following wetting and drying paths were determined. The material was the same used to manufacture the disposal cells of the Spanish surface facility of El Cabril. The water retention capacity of mortar is clearly higher than that of concrete when expressed as gravimetric water content, but the difference reduces when it is expressed as degree of saturation. Hysteresis between wetting and drying was observed for both materials, particularly for mortar. The tests went on for very long periods of time, and concerns about the geochemical, mineralogical and porosity changes occurred in the materials during the determinations (changes in dry mass, grain density, samples volume) and their repercussion on the results obtained (water content and degree of saturation computation) were raised. Also, the fact of having used techniques applying total and matrix suction could have affected the results. (authors)

  20. Sources, extent and history of methane seepage on the continental shelf off northern Norway

    Science.gov (United States)

    Sauer, Simone; Lepland, Aivo; Chand, Shyam; Schubert, Carsten J.; Eichinger, Florian; Knies, Jochen

    2014-05-01

    Active natural hydrocarbon gas seepage was recently discovered in the Hola area on the continental shelf off Vesterålen, northern Norway. We conducted acoustic and geochemical investigations to assess the modern and past extent, source and pathways of the gas seepage . Water column echosounder surveys showed bubble plumes up to several tens of metres above the seafloor. Analyses of dissolved methane in the water column indicated slightly elevated concentrations (50 nM) close to the seafloor. To identify fluxes and origin of methane in the sediments we analysed sediment pore water chemistry, the isotopic composition of methane and of dissolved inorganic carbon (d13CCH4, d2HCH4, d13CDIC) in three closely spaced (

  1. The origin of elevated water levels in emplacement boreholes, Pahute Mesa, Nevada Test Site: A numerical study

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, G.G.; Brikowski, T.H.

    1993-12-01

    The origin of elevated water levels in emplacement boreholes at Pahute Mesa, Nevada Test Site, is uncertain. If the water is from naturally perched aquifers, then presumed ``above water table`` weapons tests may directly impact the groundwater quality. The purpose of this study is to determine the probable source of the elevated water in boreholes by comparing modeled seepage of infiltrated drilling fluids, and the seepage from a simulated naturally perched aquifer with the observed water level history. In the model, large volumes of water are infiltrated, yet return flow of fluids back into the hole stops within three days after the end of drilling and is insufficient to produce observed standing water. Return flow is limited for two reasons: (1) the volume of the saturated rock next to the borehole is small; (2) pressure head gradient direct unsaturated flow away from the borehole. Simulation of seepage from a naturally perched aquifer readily reproduces the observed water levels.

  2. Shallow rainwater lenses in deltaic areas with saline seepage

    NARCIS (Netherlands)

    Louw, de P.G.B.; Eeman, S.; Siemon, B.; `Voortman, B.R.; Gunnink, J.; Baaren, E.S.; Oude Essink, G.H.P.

    2011-01-01

    In deltaic areas with saline seepage, freshwater availability is often limited to shallow rainwater lenses lying on top of saline groundwater. Here we describe the characteristics and spatial variability of such lenses in areas with saline seepage and the mechanisms that control their occurrence and

  3. DETERMINANTS OF RESIDENTIAL PER CAPITA WATER ...

    African Journals Online (AJOL)

    This report presents the findings of the study on the determinants of residential per capita water demand of Makurdi metropolis in Benue State, Nigeria. Data for the study was obtained by the use of questionnaires, oral interviews and observations. The data was analyzed using SPSS. Twenty variables were considered in ...

  4. Seepage patterns of Diuron in a ditch bed during a sequence of flood events

    International Nuclear Information System (INIS)

    Dages, C.; Samouëlian, A.; Negro, S.; Storck, V.; Huttel, O.; Voltz, M.

    2015-01-01

    Although ditches limit surface water contamination, groundwater recharge through ditches in Mediterranean catchments may result in groundwater contamination. We analysed the dynamics of pesticide percolation in ditches by conducting an original lab experiment that mimicked the successive percolation processes that occur during a flood season. Nine successive percolation events were operated on an undisturbed soil column collected from a ditch bed. The infiltrating water was doped with 14 C-Diuron at concentrations that were chosen to decrease between the events so as to correspond to values observed during actual flood events. The water and solute fluxes were monitored during each event, and the final extractable and non-extractable Diuron residues in the column were determined. Two main observations were made. First, a high leaching potential was observed through the ditch bed over a succession of infiltrating flood events, with 58.9% of the infiltrated Diuron and its metabolites leaching. Second, compared with the contamination of surface water circulating in the ditches, the contamination of seepage water exhibited smaller peak values and persisted much longer because of the desorption of Diuron residues stored in the ditch bed. Thus, ditches serve as buffering zones between surface and groundwater. However, compared with field plots, ditches appear to be a preferential location for the percolation of pesticides into groundwater at the catchment scale. - Highlights: • Diuron percolation in a ditch bed during flood events was mimicked in a column setup. • Diuron percolation can represent up to 50% of the infiltrated Diuron. • The ditch bed exhibits a high buffering capacity due to its high sorption properties. • Contamination period of percolation water lasts longer than that of infiltrating water. • Diuron residues stored in ditch bed move deeper than in field topsoils.

  5. Seepage patterns of Diuron in a ditch bed during a sequence of flood events

    Energy Technology Data Exchange (ETDEWEB)

    Dages, C., E-mail: cecile.dages@supagro.inra.fr; Samouëlian, A.; Negro, S.; Storck, V.; Huttel, O.; Voltz, M.

    2015-12-15

    Although ditches limit surface water contamination, groundwater recharge through ditches in Mediterranean catchments may result in groundwater contamination. We analysed the dynamics of pesticide percolation in ditches by conducting an original lab experiment that mimicked the successive percolation processes that occur during a flood season. Nine successive percolation events were operated on an undisturbed soil column collected from a ditch bed. The infiltrating water was doped with {sup 14}C-Diuron at concentrations that were chosen to decrease between the events so as to correspond to values observed during actual flood events. The water and solute fluxes were monitored during each event, and the final extractable and non-extractable Diuron residues in the column were determined. Two main observations were made. First, a high leaching potential was observed through the ditch bed over a succession of infiltrating flood events, with 58.9% of the infiltrated Diuron and its metabolites leaching. Second, compared with the contamination of surface water circulating in the ditches, the contamination of seepage water exhibited smaller peak values and persisted much longer because of the desorption of Diuron residues stored in the ditch bed. Thus, ditches serve as buffering zones between surface and groundwater. However, compared with field plots, ditches appear to be a preferential location for the percolation of pesticides into groundwater at the catchment scale. - Highlights: • Diuron percolation in a ditch bed during flood events was mimicked in a column setup. • Diuron percolation can represent up to 50% of the infiltrated Diuron. • The ditch bed exhibits a high buffering capacity due to its high sorption properties. • Contamination period of percolation water lasts longer than that of infiltrating water. • Diuron residues stored in ditch bed move deeper than in field topsoils.

  6. Old TNX Seepage Basin: Environmental information document

    International Nuclear Information System (INIS)

    Dunaway, J.K.; Johnson, W.F.; Kingley, L.E.; Simmons, R.V.; Bledsoe, H.W.; Smith, J.A.

    1986-12-01

    This document provides environmental information on postulated closure options for the Old TNX Seepage Basin at the Savannah River Plant and was developed as background technical documentation for the Department of Energy's proposed Environmental Impact Statement (EIS) on waste management activities for groundwater protection at the plant. The results of groundwater and atmospheric pathway analyses, accident analysis, and other environmental assessments discussed in this document are based upon a conservative analysis of all foreseeable scenarios as defined by the National Environmental Policy Act (40 CFR 1500-1508). The scenarios do not necessarily represent actual environmental conditions. This document is not meant to be used as a regulatory closure plan or other regulatory document to comply with required federal or state environmental regulations

  7. A pragmatic method for estimating seepage losses for small reservoirs with application in rural India

    Science.gov (United States)

    Oblinger, Jennifer A.; Moysey, Stephen M. J.; Ravindrinath, Rangoori; Guha, Chiranjit

    2010-05-01

    SummaryThe informal construction of small dams to capture runoff and artificially recharge ground water is a widespread strategy for dealing with water scarcity. A lack of technical capacity for the formal characterization of these systems, however, is often an impediment to the implementation of effective watershed management practices. Monitoring changes in reservoir storage provides a conceptually simple approach to quantify seepage, but does not account for the losses occurring when seepage is balanced by inflows to the reservoir and the stage remains approximately constant. To overcome this problem we evaluate whether a physically-based volume balance model that explicitly represents watershed processes, including reservoir inflows, can be constrained by a limited set of data readily collected by non-experts, specifically records of reservoir stage, rainfall, and evaporation. To assess the impact of parameter non-uniqueness associated with the calibration of the non-linear model, we perform a Monte Carlo analysis to quantify uncertainty in the total volume of water contributed to the subsurface by the 2007 monsoon for a dam located in the Deccan basalts near the village of Salri in Madhya Pradesh, India. The Monte Carlo analysis demonstrated that subsurface losses from the reservoir could be constrained with the available data, but additional measurements are required to constrain reservoir inflows. Our estimate of seepage from the reservoir (7.0 ± 0.6 × 10 4 m 3) is 3.5 times greater than the recharge volume estimated by considering reservoir volume changes alone. This result suggests that artificial recharge could be significantly underestimated when reservoir inflows are not explicitly included in models. Our seepage estimate also accounts for about 11% of rainfall occurring upstream of the dam and is comparable in magnitude to natural ground water recharge, thereby indicating that the reservoir plays a significant role in the hydrology of this small

  8. Determination of 46Sc in water

    International Nuclear Information System (INIS)

    Huo Bijun; Ji Zhaogang; Wang Juying

    1985-01-01

    Analytical procedures for the determination of 46 Sc in water is presented. 46 Sc in water is concentrated with Fe(OH) 3 ; Then 46 Sc is extracted with TBP and purified by precipitating it with Amygdalic Acid. Finally the precipitate is ignited into Sc 2 O 3 under 800 deg C and β-activity is counted. In this method chemical reeovery for Sc was (90.8 +- 2.8)% and radiochemical recovery for 46 Sc was (89.8 +- 3.8)%. Purification factors for some of the relevant Radionuclides ranged from 10 3 to 10 5

  9. Laboratorial studies on the seepage impact in open-channel flow turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Herrera Granados, Oscar; Kostecki, Stanislaw, E-mail: Oscar.Herrera-Granados@pwr.wroc.pi [Institute of Geotechnics and Hydro-engineering (I-10), Wroclaw University of Technology. Plac Grunwaldzki 9 D-2 p.112. 50-377 Wroclaw (Poland)

    2011-12-22

    In natural streams, the interaction between water in motion and movable beds derives in transport of material. This is a fact that causes several problems for river regulation, above all in streams which were heavily modified by human interferences. Therefore, to find solutions or at least to alleviate the negative effects that sediment transport can bring with is a topic to be researched. The impact of seepage on river sedimentation processes and open-channel flow is important for environmental issues but it is commonly neglected by water specialists. The present contribution presents the output of a series of experimental works where the influence of seepage on the open channel turbulence is analyzed at the laboratory scale. Even though that the magnitude of the groundwater flow is significantly smaller than the magnitude of the open channel flow; the output of the experiments demonstrates that seepage not only modifies the water-sediment interaction as demonstrated Herrera Granados (2008; 2010); but also is affecting the velocity field and turbulence dynamics of the open-channel flow.

  10. Laboratorial studies on the seepage impact in open-channel flow turbulence

    International Nuclear Information System (INIS)

    Herrera Granados, Oscar; Kostecki, Stanislaw

    2011-01-01

    In natural streams, the interaction between water in motion and movable beds derives in transport of material. This is a fact that causes several problems for river regulation, above all in streams which were heavily modified by human interferences. Therefore, to find solutions or at least to alleviate the negative effects that sediment transport can bring with is a topic to be researched. The impact of seepage on river sedimentation processes and open-channel flow is important for environmental issues but it is commonly neglected by water specialists. The present contribution presents the output of a series of experimental works where the influence of seepage on the open channel turbulence is analyzed at the laboratory scale. Even though that the magnitude of the groundwater flow is significantly smaller than the magnitude of the open channel flow; the output of the experiments demonstrates that seepage not only modifies the water-sediment interaction as demonstrated Herrera Granados (2008; 2010); but also is affecting the velocity field and turbulence dynamics of the open-channel flow.

  11. Infinite slope stability under steady unsaturated seepage conditions

    Science.gov (United States)

    Lu, Ning; Godt, Jonathan W.

    2008-01-01

    We present a generalized framework for the stability of infinite slopes under steady unsaturated seepage conditions. The analytical framework allows the water table to be located at any depth below the ground surface and variation of soil suction and moisture content above the water table under steady infiltration conditions. The framework also explicitly considers the effect of weathering and porosity increase near the ground surface on changes in the friction angle of the soil. The factor of safety is conceptualized as a function of the depth within the vadose zone and can be reduced to the classical analytical solution for subaerial infinite slopes in the saturated zone. Slope stability analyses with hypothetical sandy and silty soils are conducted to illustrate the effectiveness of the framework. These analyses indicate that for hillslopes of both sandy and silty soils, failure can occur above the water table under steady infiltration conditions, which is consistent with some field observations that cannot be predicted by the classical infinite slope theory. A case study of shallow slope failures of sandy colluvium on steep coastal hillslopes near Seattle, Washington, is presented to examine the predictive utility of the proposed framework.

  12. Determination of mercury in drinking water

    International Nuclear Information System (INIS)

    Anand, S.J.S.

    1976-01-01

    Determination of mercury in drinking water samples have been carried out by neutron activation followed by chemical separation. The chemical analysis is necessary as the levels of mercury in these samples are quite low and activities of sodium, copper etc. interfere in its determination by direct spectroscopy. Solvent extraction separation offers speed and complete separation from interfering activities. Some of drinking water samples collected at Trombay have been analysed and their result are given in this paper. The procedure was checked with 197 Hg tracer and the reproducibility of the procedure is within 5%. It was free from contamination due to the activities of Cu, Na etc. The time of analysis was 15 minutes, and upto 5 samples could be analysed conveniently at a time. The average chemical yield was 72%. (T.I.)

  13. Determination of Th-230 in water

    International Nuclear Information System (INIS)

    Oliveira Melo, M.A.M. de

    1990-01-01

    On of the current goals of the Radiochemistry Division of CDTN is to acquire capability in determining contaminants of high radiotoxicity in different matrixes. The method described here was developed in order to determine Th-230 in water, one of the decay products of the uranium series, belongs to the most restrictive class of radionuclides, on account of its alpha emission and half-life of 8 x 10 4 years. The method conesists of two radiochemical steps, one electrodeposition step and alpha spectrometry with the use of a surface-barrier detector. Water samples with internal Th-230 standards were analysed and the results showed good reproducibility with erros a around 10% and alfa detection efficiency of 12%. The lower detection limit is around 0,4 Bq/l. (author) [pt

  14. Investigation of seepage under the Wenxiakou dam using radiotracer

    International Nuclear Information System (INIS)

    Li Zhangsu

    1988-01-01

    This paper describes the result of seepage observation on the dam foundation of Wenxiakou Reservoir using radioactive NaI (I-131) as a tracer. The main feature of the observing technique is to ascertain the seepages between the dam foundation and the clay core wall and around the abutment by measuring vertical flow. The results obtained from the observation have provided some important information for planning the engineering project of anti-seepage and reinforcement of the dam foundation and its right abutment. (author). 2 refs, 4 figs, 1 tab

  15. The analysis of physicochemical characteristics of pig farm seepage ...

    African Journals Online (AJOL)

    Dikonketso Matjuda

    -bodies, promoting ... that the seepage from pig farm degraded the natural environment by causing eutrophication, promote ... mainly livestock droppings, heavy metals, fertilizers and ... from microorganisms to insects, birds, fish, and at the.

  16. modelingthe effect the effect of contact and seepage forces

    African Journals Online (AJOL)

    eobe

    This research work has investigated the contribution of contact force and seepage force to the ... e equilibrium model has deduced an expression for the safe hydraulic head during well ...... Plastic deformation of soils simulation using DEM,.

  17. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    Energy Technology Data Exchange (ETDEWEB)

    E. Gonnenthal; N. Spyoher

    2001-02-05

    The purpose of this Analysis/Model Report (AMR) is to document the Near-Field Environment (NFE) and Unsaturated Zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrologic-chemical (THC) processes on unsaturated zone flow and transport. This is in accordance with the ''Technical Work Plan (TWP) for Unsaturated Zone Flow and Transport Process Model Report'', Addendum D, Attachment D-4 (Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) 2000 [153447]) and ''Technical Work Plan for Nearfield Environment Thermal Analyses and Testing'' (CRWMS M and O 2000 [153309]). These models include the Drift Scale Test (DST) THC Model and several THC seepage models. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal loading conditions, and predict the chemistry of waters and gases entering potential waste-emplacement drifts. The intended use of this AMR is to provide input for the following: (1) Performance Assessment (PA); (2) Abstraction of Drift-Scale Coupled Processes AMR (ANL-NBS-HS-000029); (3) UZ Flow and Transport Process Model Report (PMR); and (4) Near-Field Environment (NFE) PMR. The work scope for this activity is presented in the TWPs cited above, and summarized as follows: continue development of the repository drift-scale THC seepage model used in support of the TSPA in-drift geochemical model; incorporate heterogeneous fracture property realizations; study sensitivity of results to changes in input data and mineral assemblage; validate the DST model by comparison with field data; perform simulations to predict mineral dissolution and precipitation and their effects on fracture properties and chemistry of water (but not flow rates) that may seep into drifts; submit modeling results to the TDMS and document the models. The model development, input data

  18. Flame photometric determination of strontium in water

    Science.gov (United States)

    Skougstad, Marvin W.

    1957-01-01

    Preliminary search of reported methods of Sr analysis revealed several investigations which have been made for the determination of Sr with the flame photometer, both at relatively low concentrations (0 to 50 ppm Sr) and at higher concentrations. Generally the procedures described involved measurement of Sr emission at either 460.7 mu or at 681 mu. There is disagreement among those reporting methods for Sr as to the preference of the one wavelength over the other. The 681 line (or band) seems to be preferred because of its greater reproducibility and relative freedom from interference. The 460.7 mu line, however, lies in the region of greater sensitivity of the photomultiplier tube, and hence for this reason is preferred by some. This is an advantage, of course, when determining Sr at very low concentrations. This investigation is concerned with determining the optimum conditions for the determination of Sr at low concentration levels in water samples. Early experimental work indicated a greater sensitivity for the 460.7 mu (hereafter designated as 461 mu) Sr line. Therefore, most of the subsequent work was based on a study of the effects of various other materials and conditions on the emission of Sr at this wavelength.

  19. Stream seepage and groundwater levels, Wood River Valley, south-central Idaho, 2012-13

    Science.gov (United States)

    Bartolino, James R.

    2014-01-01

    Stream discharge and water levels in wells were measured at multiple sites in the Wood River Valley, south-central Idaho, in August 2012, October 2012, and March 2013, as a component of data collection for a groundwater-flow model of the Wood River Valley aquifer system. This model is a cooperative and collaborative effort between the U.S. Geological Survey and the Idaho Department of Water Resources. Stream-discharge measurements for determination of seepage were made during several days on three occasions: August 27–28, 2012, October 22–24, 2012, and March 27–28, 2013. Discharge measurements were made at 49 sites in August and October, and 51 sites in March, on the Big Wood River, Silver Creek, their tributaries, and nearby canals. The Big Wood River generally gains flow between the Big Wood River near Ketchum streamgage (13135500) and the Big Wood River at Hailey streamgage (13139510), and loses flow between the Hailey streamgage and the Big Wood River at Stanton Crossing near Bellevue streamgage (13140800). Shorter reaches within these segments may differ in the direction or magnitude of seepage or may be indeterminate because of measurement uncertainty. Additional reaches were measured on Silver Creek, the North Fork Big Wood River, Warm Springs Creek, Trail Creek, and the East Fork Big Wood River. Discharge measurements also were made on the Hiawatha, Cove, District 45, Glendale, and Bypass Canals, and smaller tributaries to the Big Wood River and Silver Creek. Water levels in 93 wells completed in the Wood River Valley aquifer system were measured during October 22–24, 2012; these wells are part of a network established by the U.S. Geological Survey in 2006. Maps of the October 2012 water-table altitude in the unconfined aquifer and the potentiometric-surface altitude of the confined aquifer have similar topology to those on maps of October 2006 conditions. Between October 2006 and October 2012, water-table altitude in the unconfined aquifer rose by

  20. A Model of Anisotropic Property of Seepage and Stress for Jointed Rock Mass

    Directory of Open Access Journals (Sweden)

    Pei-tao Wang

    2013-01-01

    Full Text Available Joints often have important effects on seepage and elastic properties of jointed rock mass and therefore on the rock slope stability. In the present paper, a model for discrete jointed network is established using contact-free measurement technique and geometrical statistic method. A coupled mathematical model for characterizing anisotropic permeability tensor and stress tensor was presented and finally introduced to a finite element model. A case study of roadway stability at the Heishan Metal Mine in Hebei Province, China, was performed to investigate the influence of joints orientation on the anisotropic properties of seepage and elasticity of the surrounding rock mass around roadways in underground mining. In this work, the influence of the principal direction of the mechanical properties of the rock mass on associated stress field, seepage field, and damage zone of the surrounding rock mass was numerically studied. The numerical simulations indicate that flow velocity, water pressure, and stress field are greatly dependent on the principal direction of joint planes. It is found that the principal direction of joints is the most important factor controlling the failure mode of the surrounding rock mass around roadways.

  1. Spectrophotometric determination of silica in water. Low range

    International Nuclear Information System (INIS)

    Acosta L, E.

    1992-07-01

    The spectrophotometric method for the determination of the silica element in water, demineralized water, raw waters, laundry waters, waters treated with ion exchange resins and sea waters is described. This method covers the determination of the silica element in the interval from 20 to 1000 μg/l on 50 ml. of base sample. These limits its can be variable if the size of the used aliquot one is changed for the final determination of the silica element. (Author)

  2. Effects of Uncertainty and Spatial Variability on Seepage into Drifts in the Yucca Mountain Total system Performance Assessment Model

    International Nuclear Information System (INIS)

    Kalinich, D. A.; Wilson, M. L.

    2001-01-01

    Seepage into the repository drifts is an important factor in total-system performance. Uncertainty and spatial variability are considered in the seepage calculations. The base-case results show 13.6% of the waste packages (WPs) have seepage. For 5th percentile uncertainty, 4.5% of the WPs have seepage and the seepage flow decreased by a factor of 2. For 95th percentile uncertainty, 21.5% of the WPs have seepage and the seepage flow increased by a factor of 2. Ignoring spatial variability resulted in seepage on 100% of the WPs, with a factor of 3 increase in the seepage flow

  3. Simulation of 2-dimensional subsurface seepage flow in an anisotropic porous medium

    Directory of Open Access Journals (Sweden)

    Chhaya K. Lande

    2016-09-01

    Full Text Available In this study, we develop new analytical solution to estimate the transient behavior of phreatic surface in an anisotropic unconfined aquifer which is overlying a leaky base and subjected to multiple recharge and withdrawal. The hydrologic setting consists of a rectangular unconfined leaky aquifer adjacent to two water bodies of constant water head along the opposite faces of the aquifer. The remaining two faces of the aquifer have no flow conditions. The flow of seepage is approximated using two-dimensional Boussinesq equation, and solved analytically using mixed finite Fourier transform. Application of the new solution is demonstrated using an illustrative example.

  4. Application of short-range photogrammetry for monitoring seepage erosion of riverbank by laboratory experiments

    Science.gov (United States)

    Masoodi, A.; Noorzad, A.; Majdzadeh Tabatabai, M. R.; Samadi, A.

    2018-03-01

    Temporal and spatial monitoring play a significant role in evaluating and examining the riverbank morphology and its spatiotemporal changes. Unlike the terrestrial laser scanners, other previously used methods such as satellite images, total station surveying, and erosion pins have limited application to quantify the small-scale bank variations due to the lack of rapid survey and resolution in data acquisition. High cost, lack of availability, specialized equipment and hard movement of laser scanners make it necessary to develop new accurate, economical and easily available methods. The present study aims to test the Kinect photogrametric technology for measuring and assessing riverbank variations in laboratory environment. For this purpose, three models of layered soil blocks for three different levels of groundwater (i.e. 24, 34 and 44 cm) were designed to investigate the seepage erosion behavior experimentally. The results indicate the high accuracy of Kinect in measuring the bank erosion cavity dimensions (i.e., 0.5% error) with high spatial resolution data (i.e. 300,000 points per frame). The high speed of Kinect in riverbank scanning enables the analysis of time variations of mechanisms such as seepage erosion which occurs rather rapidly. The results confirmed that there is a power relationship between the seepage gradient and the time of the bank failure with a determination coefficient of 0.97. Moreover, an increase in the level of groundwater on the riverbank increases the rate of undercutting retreat that caused more rapid failure of the riverbank.

  5. Testing and modeling of seepage into underground openings in a heterogeneous fracture system at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Ahlers, C.F.; Trautz, R.C.; Cook, P.J.; Finsterle, S.

    2002-01-01

    We discuss field activities designed to characterize seepage into an underground opening at the potential site for geologic storage of high-level radioactive waste (HLRW) at Yucca Mountain, Nevada, and the use of these data for development and calibration of a model for predicting seepage into planned HLRW emplacement drifts. Air-injection tests were conducted to characterize the permeability of the fractured rock, and liquid-release tests (LRTs) were conducted and seepage monitored to characterize the seepage-relevant properties of the fractured rock. Both air-injection and liquid-release tests were performed in the same borehole intervals, located above the underground openings. For modeling, three-dimensional, heterogeneous permeability fields were generated, conditioned on the air-permeability data. The initial seepage data collected were used to calibrate the model and test the appropriateness of the modeling approach. A capillary-strength parameter and porosity were the model parameters selected for estimation by data inversion. However, due to the short-term nature of the initial data, the inversion process was unable to independently determine the capillary strength and porosity of the fractured rock. Subsequent seepage data collection focused on longer-term tests, a representative selection of which was used for data inversion. Field observations also played a key role by identifying factors such as evaporation and ceiling geometry that can enhance or reduce seepage. These observations help guide future test and model development by ensuring that relevant processes that influence seepage are identified, characterized, and incorporated into the model, thus increasing confidence in the parameter estimates. It is this iterative and collaborative approach to field testing and modeling, and the feedback mechanisms of field-test-methodology and model review and revision, that has been employed to continuously improve the scientific quality of the study

  6. Standards for heavy water concentration determinations in light water

    International Nuclear Information System (INIS)

    Varlam, M.; Steflea, D.; Pavelescu, M.

    1995-01-01

    The paper presents a method to prepare heavy water -light water standards within the range 144 ppm - 1%. A formula for computing standards concentration based on initial concentration of D 2 O and distilled water is given

  7. Water analysis. Determination of elements by atomic absorption

    International Nuclear Information System (INIS)

    Anon.

    Analysis of homogeneous water solutions (plain water, polluted waters, effluents...) by atomic absorption spectrometry with correction for non specific absorption. The quantity ratio is determined by comparison with standard solutions, correction tables are given [fr

  8. Determination of water quality index and portability of Iguedo stream ...

    African Journals Online (AJOL)

    Determination of water quality index and portability of Iguedo stream in Edo ... has been found functional in assessing the water quality of this stream based on the ... Key words: Water quality index, physicochemical parameters, Iguedo Stream.

  9. Interpretation of self-potential data for dam seepage investigations

    Energy Technology Data Exchange (ETDEWEB)

    Corwin, R.F.; Sheffer, M.R.; Salmon, G. [BC Hydro, Burnaby, BC (Canada)

    2007-04-15

    This book represents one of a series on the subject of geophysical methods and their use in assessing seepage and internal erosion in embankment dams. This manual facilitates the interpretation of self-potential (SP) data generated by subsurface fluid flow, with an emphasis on dam seepage studies. It is intended for users with a background in geophysics or engineering having a general familiarity with both the SP and direct-current (DC) resistivity methods and their applications. It includes an extensive reference list covering all aspects of available SP interpretation techniques, including qualitative, analytical and numerical methods. Particular emphasis is placed on the use of geometric source analytical modeling methods to evaluate SP anomalies. These methods provide a simple yet efficient means of estimating the location and depth of current sources of observed SP data, which may be linked to fluid flow in the subsurface. The manual is primarily oriented toward embankment dams and earthen structures such as levees and dikes. SP methods have been used to investigate seepage through pervious zones and cracks in concrete and concrete-faced structures. The manual describes the nature of SP fields generated by both uniform and non-uniform dam seepage flow, as well as non-seepage sources of SP variations. These methods enable the study of more complex systems and require a more comprehensive analysis of a given field site. refs., tabs., figs.

  10. Determination of Phthalates in Drinking Water Samples

    African Journals Online (AJOL)

    user

    successfully applied to the analysis of phthalate esters contamination in bottled drinking water samples. ... esters are used in the manufacturing of polyvinyl chloride. (PVC). ... water, soil, air, food products and the human body. (Castillo et al.

  11. Determination of crystal water in uranium tetrafluoride

    International Nuclear Information System (INIS)

    Cheng Yingfang

    1991-01-01

    A gravimetric method for measuring crystal water in uranium tetrafluoride is reported. Being convenient, reliable and quick, it can be used as a routine analytical method measure crystal water in uranium tetrafluoride, thorium tetrafluoride etc

  12. Determining water management training needs through stakeholder ...

    African Journals Online (AJOL)

    South Africa is a water-stressed country and the efficient management of the demand for and frugal use of water is a topic that can no longer be avoided. Community-based natural resource management is an alternative approach to government stewardship of natural resources, and in the instance of water management it is ...

  13. Infiltration, seepage and slope instability mechanisms during the 20–21 November 2000 rainstorm in Tuscany, central Italy

    Directory of Open Access Journals (Sweden)

    V. Tofani

    2006-01-01

    Full Text Available On 20–21 November 2000, a storm of high intensity, with a estimated return period of more than 100 years, triggered over 50 landslides within the province of Pistoia in Tuscany (Italy. These failures can be defined as complex earth slides- earth flows. One of the documented landslides has been investigated by modelling the ground water infiltration process, the positive and negative pore water pressure variations and the effects of these variations on slope stability during the rainfall event. Morphometric and geotechnical analyses were carried out through a series of in-situ and laboratory tests, the results of which were used as input for the modelling process. The surface infiltration rate was initially simulated using the rainfall recorded at the nearest raingauge station. Finite element seepage analysis for transient conditions were then employed to model the changes in pore water pressure during the storm event, using the computed infiltration rate as the ground surface boundary condition. Finally, the limit equilibrium slope stability method was applied to calculate the variations in the factor of safety during the event and thereby determine the critical time of instability. For the investigated site the trend of the factor of safety indicates that the critical time for failure occurs about 18 h after the storm commences, and highlights the key role played by the soil permeability and thickness in controlling the response in terms of slope instability.

  14. Unsaturated Seepage Analysis of Cracked Soil including Development Process of Cracks

    Directory of Open Access Journals (Sweden)

    Ling Cao

    2016-01-01

    Full Text Available Cracks in soil provide preferential pathways for water flow and their morphological parameters significantly affect the hydraulic conductivity of the soil. To study the hydraulic properties of cracks, the dynamic development of cracks in the expansive soil during drying and wetting has been measured in the laboratory. The test results enable the development of the relationships between the cracks morphological parameters and the water content. In this study, the fractal model has been used to predict the soil-water characteristic curve (SWCC of the cracked soil, including the developmental process of the cracks. The cracked expansive soil has been considered as a crack-pore medium. A dual media flow model has been developed to simulate the seepage characteristics of the cracked expansive soil. The variations in pore water pressure at different part of the model are quite different due to the impact of the cracks. This study proves that seepage characteristics can be better predicted if the impact of cracks is taken into account.

  15. F-Area Seepage Basins Groundwater Monitoring Report: Volume 1, Third and fourth quarters 1994

    International Nuclear Information System (INIS)

    Chase, J.A.

    1994-03-01

    Isoconcentration/isoactivity maps included in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units. Geologic cross sections indicate both the extent and depth of contamination of the primary contaminants in all of the hydrostratigraphic units during the second half of 1994. Water-level maps indicate that the groundwater flow rates and directions at the F-Area Seepage Basins have remained relatively constant since the basins ceased to be active in 1988

  16. Contribution to atmospheric methane by natural seepages on the Bulgarian continental shelf

    Energy Technology Data Exchange (ETDEWEB)

    Dimitrov, L. [Bulgarian Academy of Science, Varna (Bulgaria). Inst. of Oceanology

    2002-07-01

    This paper provides an estimation of the atmospheric methane flux from Bulgarian Black Sea continental shelf. Potential gas source rocks include Holocene gas-charged sediments, Quaternary peats and sapropels, and deep-lying Palaeocene and Neogene clays, Cretaceous coals, and other sediments of late Jurassic to early Cretaceous age. These cover almost the whole continental shelf and slope and, together with irregularly developed seal rocks and widespread active and conducting faults, provide good conditions for upward gas migration. A total of 5 100 line kilometers of shallow seismic (boomer) and echo-sounder records acquired during the Institute of Oceanology's regional surveys, and several detailed side-scan sonar lines, have been reviewed for water column targets. Four hundred and eighty-two targets were assigned as gas seepage plumes. It is estimated that a total of 19,735 individual seeps exists on the open shelf. The number of seeps in coastal waters was estimated to be 6020; this is based on available public-domain data, specific research, and results of a specially made questionnaire which was distributed to a range of 'seamen'. More than 150 measurements of the seabed flux rates were made in the 'Golden sands' and 'Zelenka' seepage areas between 1976 and 1991. Indirect estimations of flux rates from video and photo materials, and a review of published data have also been undertaken. Based on these data, three types of seepages were identified as the most representative of Bulgarian coastal waters. These have flux rates of 0.4, 1.8, and 3.51/min. The contribution to atmospheric methane is calculated by multiplying the flux rates with the number of seepages, and entering corrections for methane concentration and the survival of gas bubbles as they ascend through seawater of the corresponding water depth. The estimation indicates that between 45,100,000 (0.03 Tg) and 210,650,000 m{sup 3} (0. 15 Tg) methane yr{sup -1} come

  17. H-Area Seepage Basins Groundwater Monitoring Report: Volume 1, Third and Fourth quarters 1994

    International Nuclear Information System (INIS)

    Chase, J.A.

    1994-03-01

    Isoconcentration/isocactivity maps included in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units during the second half of 1994. Geologic cross sections indicate both the extent and depth of contamination of the primary contaminants in all of the hydrostratigraphic units during the second half of 1994. Water-level maps indicate that the groundwater flow rates and directions at the H-Area Seepage Basins have remained relatively constant since the basins ceased to be active in 1988

  18. Environmental hazards from natural hydrocarbons seepage: Integrated classification of risk from sediment chemistry, bioavailability and biomarkers responses in sentinel species

    International Nuclear Information System (INIS)

    Benedetti, Maura; Gorbi, Stefania; Fattorini, Daniele; D'Errico, Giuseppe; Piva, Francesco; Pacitti, Davide; Regoli, Francesco

    2014-01-01

    Potential effects of natural emissions of hydrocarbons in the marine environment have been poorly investigated. In this study, a multidisciplinary weight of evidence (WOE) study was carried out on a shallow seepage, integrating sediment chemistry with bioavailability and onset of subcellular responses (biomarkers) in caged eels and mussels. Results from different lines of evidence (LOEs) were elaborated within a quantitative WOE model which, based on logical flowcharts, provide synthetic indices of hazard for each LOE, before their integration in a quantitative risk assessment. Evaluations of different LOEs were not always in accordance and their overall elaboration summarized as Moderate the risk in the seepage area. This study provided first evidence of biological effects in organisms exposed to natural hydrocarbon emissions, confirming the limit of chemical characterization as stand-alone criteria for environmental quality assessment and the utility of multidisciplinary investigations to determine the good environmental status as required by Environmental Directives. -- Highlights: • Hazards from natural seepage were evaluated through a multidisciplinary WOE study. • Caged eels and mussels were chosen as bioindicator organisms. • Evaluations obtained from various LOEs were not always in accordance. • Biological effects of natural hydrocarbons release were demonstrated. • WOE approach could discriminate different levels of hazard in low impacted conditions. -- A multidisciplinary WOE study in a shallow coastal seepage summarized a Moderate level of risk based on integration of sediment chemistry with biological effects in caged organisms

  19. Albedo and land surface temperature shift in hydrocarbon seepage potential area, case study in Miri Sarawak Malaysia

    Science.gov (United States)

    Suherman, A.; Rahman, M. Z. A.; Busu, I.

    2014-02-01

    The presence of hydrocarbon seepage is generally associated with rock or mineral alteration product exposures, and changes of soil properties which manifest with bare development and stress vegetation. This alters the surface thermodynamic properties, changes the energy balance related to the surface reflection, absorption and emission, and leads to shift in albedo and LST. Those phenomena may provide a guide for seepage detection which can be recognized inexpensively by remote sensing method. District of Miri is used for study area. Available topographic maps of Miri and LANDSAT ETM+ were used for boundary construction and determination albedo and LST. Three land use classification methods, namely fixed, supervised and NDVI base classifications were employed for this study. By the intensive land use classification and corresponding statistical comparison was found a clearly shift on albedo and land surface temperature between internal and external seepage potential area. The shift shows a regular pattern related to vegetation density or NDVI value. In the low vegetation density or low NDVI value, albedo of internal area turned to lower value than external area. Conversely in the high vegetation density or high NDVI value, albedo of internal area turned to higher value than external area. Land surface temperature of internal seepage potential was generally shifted to higher value than external area in all of land use classes. In dense vegetation area tend to shift the temperature more than poor vegetation area.

  20. Albedo and land surface temperature shift in hydrocarbon seepage potential area, case study in Miri Sarawak Malaysia

    International Nuclear Information System (INIS)

    Suherman, A; Rahman, M Z A; Busu, I

    2014-01-01

    The presence of hydrocarbon seepage is generally associated with rock or mineral alteration product exposures, and changes of soil properties which manifest with bare development and stress vegetation. This alters the surface thermodynamic properties, changes the energy balance related to the surface reflection, absorption and emission, and leads to shift in albedo and LST. Those phenomena may provide a guide for seepage detection which can be recognized inexpensively by remote sensing method. District of Miri is used for study area. Available topographic maps of Miri and LANDSAT ETM+ were used for boundary construction and determination albedo and LST. Three land use classification methods, namely fixed, supervised and NDVI base classifications were employed for this study. By the intensive land use classification and corresponding statistical comparison was found a clearly shift on albedo and land surface temperature between internal and external seepage potential area. The shift shows a regular pattern related to vegetation density or NDVI value. In the low vegetation density or low NDVI value, albedo of internal area turned to lower value than external area. Conversely in the high vegetation density or high NDVI value, albedo of internal area turned to higher value than external area. Land surface temperature of internal seepage potential was generally shifted to higher value than external area in all of land use classes. In dense vegetation area tend to shift the temperature more than poor vegetation area

  1. 工业活塞式冷水机组冷媒系统进水事故的处理%Handing of Water Seepage Accident of Cooling - medium System for Industrial Piston Chiller

    Institute of Scientific and Technical Information of China (English)

    刘文军

    2011-01-01

    The accident reason for industrial piston water chilling unit with oxygen making industry was analyzed,it was definited processing measure and verify result.%对制氧行业工业用冷水机组进水事故进行了因为分析,确定了处理措施,并验证了处理结果.

  2. Spectrophotometric determination of silica in water with Hach equipment

    International Nuclear Information System (INIS)

    Acosta L, E.

    1992-06-01

    The method for the determination of the silica element in water, demineralized water, raw waters, laundry waters, waters treated with ion exchange resins and sea waters using the indicated technique in the operation manual of the Hach equipment with a DR/3 spectrophotometer is described. This method covers the determination of the silica element in the interval from 0 to 1.5 mg/l on 50 ml. of base sample. These limits its can be variable if the size of the used aliquot one is changed for the final determination of the silica element. (Author)

  3. Fiber Bragg grating-based performance monitoring of a slope model subjected to seepage

    Science.gov (United States)

    Zhu, Hong-Hu; Shi, Bin; Yan, Jun-Fan; Zhang, Jie; Zhang, Cheng-Cheng; Wang, Bao-Jun

    2014-09-01

    In the past few years, fiber optic sensing technologies have played an increasingly important role in the health monitoring of civil infrastructures. These innovative sensing technologies have recently been successfully applied to the performance monitoring of a series of geotechnical structures. Fiber optic sensors have shown many unique advantages in comparison with conventional sensors, including immunity to electrical noise, higher precision and improved durability and embedding capabilities; fiber optic sensors are also smaller in size and lighter in weight. In order to explore the mechanism of seepage-induced slope instability, a small-scale 1 g model test of the soil slope has been performed in the laboratory. During the model’s construction, specially fabricated sensing fibers containing nine fiber Bragg grating (FBG) strain sensors connected in a series were horizontally and vertically embedded into the soil mass. The surcharge load was applied on the slope crest, and the groundwater level inside of the slope was subsequently varied using two water chambers installed besides the slope model. The fiber optic sensing data of the vertical and horizontal strains within the slope model were automatically recorded by an FBG interrogator and a computer during the test. The test results are presented and interpreted in detail. It is found that the gradually accumulated deformation of the slope model subjected to seepage can be accurately captured by the quasi-distributed FBG strain sensors. The test results also demonstrate that the slope stability is significantly affected by ground water seepage, which fits well with the results that were calculated using finite element and limit equilibrium methods. The relationship between the strain measurements and the safety factors is further analyzed, together with a discussion on the residual strains. The performance evaluation of a soil slope using fiber optic strain sensors is proved to be a potentially effective

  4. Fiber Bragg grating-based performance monitoring of a slope model subjected to seepage

    International Nuclear Information System (INIS)

    Zhu, Hong-Hu; Shi, Bin; Yan, Jun-Fan; Zhang, Cheng-Cheng; Wang, Bao-Jun; Zhang, Jie

    2014-01-01

    In the past few years, fiber optic sensing technologies have played an increasingly important role in the health monitoring of civil infrastructures. These innovative sensing technologies have recently been successfully applied to the performance monitoring of a series of geotechnical structures. Fiber optic sensors have shown many unique advantages in comparison with conventional sensors, including immunity to electrical noise, higher precision and improved durability and embedding capabilities; fiber optic sensors are also smaller in size and lighter in weight. In order to explore the mechanism of seepage-induced slope instability, a small-scale 1 g model test of the soil slope has been performed in the laboratory. During the model’s construction, specially fabricated sensing fibers containing nine fiber Bragg grating (FBG) strain sensors connected in a series were horizontally and vertically embedded into the soil mass. The surcharge load was applied on the slope crest, and the groundwater level inside of the slope was subsequently varied using two water chambers installed besides the slope model. The fiber optic sensing data of the vertical and horizontal strains within the slope model were automatically recorded by an FBG interrogator and a computer during the test. The test results are presented and interpreted in detail. It is found that the gradually accumulated deformation of the slope model subjected to seepage can be accurately captured by the quasi-distributed FBG strain sensors. The test results also demonstrate that the slope stability is significantly affected by ground water seepage, which fits well with the results that were calculated using finite element and limit equilibrium methods. The relationship between the strain measurements and the safety factors is further analyzed, together with a discussion on the residual strains. The performance evaluation of a soil slope using fiber optic strain sensors is proved to be a potentially effective

  5. Heterogeneous seepage at the Nopal I natural analogue site, Chihuahua, Mexico

    Science.gov (United States)

    Dobson, Patrick F.; Ghezzehei, Teamrat A.; Cook, Paul J.; Rodríguez-Pineda, J. Alfredo; Villalba, Lourdes; de La Garza, Rodrigo

    2012-02-01

    A study of seepage occurring in an adit at the Nopal I uranium mine in Chihuahua, Mexico, was conducted as part of an integrated natural analogue study to evaluate the effects of infiltration and seepage on the mobilization and transport of radionuclides. An instrumented seepage collection system and local automated weather station permit direct correlation between local precipitation events and seepage. Field observations recorded between April 2005 and December 2006 indicate that seepage is highly heterogeneous with respect to time, location, and quantity. Seepage, precipitation, and fracture data were used to test two hypotheses: (1) that fast flow seepage is triggered by large precipitation events, and (2) that an increased abundance of fractures and/or fracture intersections leads to higher seepage volumes. A few zones in the back adit recorded elevated seepage volumes immediately following large (>20 mm/day) precipitation events, with transit times of less than 4 h through the 8-m thick rock mass. In most locations, there is a 1-6 month time lag between the onset of the rainy season and seepage, with longer times observed for the front adit. There is a less clear-cut relation between fracture abundance and seepage volume; processes such as evaporation and surface flow along the ceiling may also influence seepage.

  6. 76 FR 7762 - Drinking Water: Regulatory Determination on Perchlorate

    Science.gov (United States)

    2011-02-11

    ...-9262-8] RIN 2040-AF08 Drinking Water: Regulatory Determination on Perchlorate AGENCY: Environmental...'s) regulatory determination for perchlorate in accordance with the Safe Drinking Water Act (SDWA... substantial likelihood that perchlorate will occur in public water systems with a frequency and at levels of...

  7. Analysis of three-dimensional transient seepage into ditch drains ...

    Indian Academy of Sciences (India)

    Ratan Sarmah

    waterlogged soils in many regions of the world, including. India [2, 6–9]—to name a ... predicting two-dimensional seepage into a network of ...... when d1 ¼ 0, the lower limits of integration of the integral ...... and agricultural development. Irrig.

  8. Heterogeneous Seepage at the Nopal I Uranium Mine, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Dobson, Patrick; Dobson, Patrick F.; Cook, Paul J.; Ghezzehei, Teamrat; Rodriguez, J. Alfredo; Garza, Rodrigo de la

    2008-01-01

    The primary objective of this analogue study is to evaluate flow and transport processes of relevance to the proposed Yucca Mountain repository. Seepage data obtained from this study will be used to constrain flow and transport models being developed for the Nopal I system

  9. Modeling of Seepage Losses in Sewage Sludge Drying Bed ...

    African Journals Online (AJOL)

    This research was carried out to develop a model governing seepage losses in sewage sludge drying bed. The model will assist in the design of sludge drying beds for effective management of wastes derived from households' septic systems. In the experiment conducted this study, 125kg of sewage sludge, 90.7% moisture ...

  10. solution of confined seepage problems below hydraulic structures

    African Journals Online (AJOL)

    user

    1985-09-01

    Sep 1, 1985 ... boundaries are used for solving the seepage problem beneath practical profiles of ... 1. INTRODUCTION. The study of flow through porous media has a wide range of .... free surface flow [3, 4, 5] and unconfined flow situations ...

  11. Optimisation of ATP determination in drinking water

    DEFF Research Database (Denmark)

    Corfitzen, Charlotte B.; Albrechtsen, Hans-Jørgen

    Adenosine Triphosphate (ATP) can be used as a relative measure of cell activity, and is measured by the light output from the reaction between luciferin and ATP catalyzed by firefly luciferase. The measurement has potential as a monitoring and surveillance tool within drinking water distribution,...... be separated from the water phase by filtration.......Adenosine Triphosphate (ATP) can be used as a relative measure of cell activity, and is measured by the light output from the reaction between luciferin and ATP catalyzed by firefly luciferase. The measurement has potential as a monitoring and surveillance tool within drinking water distribution...... and an Advance Coupe luminometer. The investigations showed a 60 times higher response of the PCP-kit, making it more suitable for measurement of samples with low ATP content. ATP-standard dilutions prepared in tap water were stable for at least 15 months when stored frozen at -80ºC, and storage of large...

  12. Determination of 40K in water samples

    International Nuclear Information System (INIS)

    Delgado, C. E.; Miranda C, L.; Cuevas J, A. K.; Vega C, H. R.

    2014-10-01

    The natural water used for human consumption comes from different sources, which may contain suspended solids in varying proportions. In groundwater, the source of suspended solids is related to the dissolution of mineral strata by the waters and leaching of rocks. Also, the radioactivity could concentrate on the bodies of slow-moving water that eventually could present a risk to ecosystems, as well as for the consumer. The water usually contains several natural radionuclides as: tritium, radon, radio, uranium isotopes, etc. The objective of this study was to evaluate the concentration of 40 K in water from different areas of Zacatecas state (Mexico). Four water samples were taken in triplicate from different areas; the 40 K concentration was measured with a spectrum metric system of gamma radiation with NaI (Tl) scintillation detector of 7.62 cm. In the measuring process a standard was prepared using water and KCl analytic grade where the 40 K concentration is 6.25 mol/Lt adding 250 mg/ml of potassium. Also the system was calibrated in energy using 3 point sources of 137 Cs, diameter 22 Na and 7.62 cm of height, using containers Marinelli and 60 Co. In the obtained spectra was observed that the photon of 1.432 MeV that emits the 40 K when decaying is the most important. The highest concentration was of 123 ± 5.2 Bq/lt and the lowest was of 9 ± 0.4 Bq/lt. Under the standards of drinking water, an amount of 40 K deposits an effective dose which contributes to annual dose received by people. (Author)

  13. Spectrophotometric Determination of Boron in Environmental Water Samples

    International Nuclear Information System (INIS)

    San San; Khin Win Kyi; Kwaw Naing

    2002-02-01

    The present paper deals with the study on the methods for the determination of boron in the environmental water samples. The standard methods which are useful for this determination are discussed thoroughly in this work. Among the standard methods approved by American Public Health Association, the carmine method was selected for this study. Prior to the determination of boron in the water samples, the precision and accuracy of the methods of choice were examined by using standard boron solutions. The determination of Boron was carried out by using water samples, waste water from Aquaculture Research Centre, University of Yangon, the Ayeyarwady River water near Magway Myathalon Pagoda in Magway Division, ground water from Sanchaung Township, and tap water from Universities' Research Centre, University of Yangon. Analyses of these water samples were done and statistical treatment of the results was carried out. (author)

  14. Methane Seepage on Mars: Where to Look and Why.

    Science.gov (United States)

    Oehler, Dorothy Z; Etiope, Giuseppe

    2017-12-01

    Methane on Mars is a topic of special interest because of its potential association with microbial life. The variable detections of methane by the Curiosity rover, orbiters, and terrestrial telescopes, coupled with methane's short lifetime in the martian atmosphere, may imply an active gas source in the planet's subsurface, with migration and surface emission processes similar to those known on Earth as "gas seepage." Here, we review the variety of subsurface processes that could result in methane seepage on Mars. Such methane could originate from abiotic chemical reactions, thermogenic alteration of abiotic or biotic organic matter, and ancient or extant microbial metabolism. These processes can occur over a wide range of temperatures, in both sedimentary and igneous rocks, and together they enhance the possibility that significant amounts of methane could have formed on early Mars. Methane seepage to the surface would occur preferentially along faults and fractures, through focused macro-seeps and/or diffuse microseepage exhalations. Our work highlights the types of features on Mars that could be associated with methane release, including mud-volcano-like mounds in Acidalia or Utopia; proposed ancient springs in Gusev Crater, Arabia Terra, and Valles Marineris; and rims of large impact craters. These could have been locations of past macro-seeps and may still emit methane today. Microseepage could occur through faults along the dichotomy or fractures such as those at Nili Fossae, Cerberus Fossae, the Argyre impact, and those produced in serpentinized rocks. Martian microseepage would be extremely difficult to detect remotely yet could constitute a significant gas source. We emphasize that the most definitive detection of methane seepage from different release candidates would be best provided by measurements performed in the ground or at the ground-atmosphere interface by landers or rovers and that the technology for such detection is currently available. Key

  15. The determination of iron-59 in water

    International Nuclear Information System (INIS)

    Zhao Min; Ban Ying

    1993-06-01

    A method to analyse iron-59 in water is introduced. The procedure of this method includes concentration by co-precipitation with hydroxides purification by anion exchange, electrodeposition in NH 4 H 2 PO 4 -(NH 4 ) 2 CO 3 system and final measurements of beta activity with a background beta-counter. The effect of iron carrier amount and pH value of water sample on the carrying Fe-59, and the effect of concentration hydrochloric acid, flowrate of adsorption and elutriation with 6 mol/L HCl-1% H 2 O 2 solution on the adsorption efficiency have been studied. The experimental results indicate that for 101 water sample, both the chemical and radiochemical yields are greater than 90%. For 51 Cr, 60 Co, 65 Zn, 95 Zr- 95 Nb and 137 Cs the decontamination factor is greater than 10 3 . The minimum detectable limit of this method is 3.8 x 10 -3 Bq/L

  16. Spectrophotometric determination of fluorides in water with Hach equipment

    International Nuclear Information System (INIS)

    Acosta L, E.

    1994-11-01

    The spectrophotometric method for the determination of the fluoride ion in water, demineralized water, raw waters, laundry waters and waters treated with ion exchange resins , using the technique and the SPADNS coloring indicated in the operation manual of the Hach equipment is described. This method covers the determination of the fluoride ion in the range from 0 to 2 mg/l on 25 ml. of radioactive base sample. These limits can be variable if the size of the used aliquot one is changed for the final determination of the fluoride ion. (Author)

  17. Determination of carbofuran in water by radioimmunoassay

    International Nuclear Information System (INIS)

    Zhu Guonian; Wu Huiming; Yang Ting; Hu Xiuqing

    2004-01-01

    A competitive radioimmunoassay (RIA) method was established to detect carbofuran in water samples. Compared with traditional analytical methods RIA provided a easy procedure with higher sensitivity. The detective limitation of RIA for carbofuran was proved to be 0.175 ng/ml. A study was performed to test validation of the RIA. In this study carbofuran residues in water samples were detected simultaneously by RIA and by high performance liquid chromatograph (HPLC). The linear correlation coefficient of the test results was measure to be 0.9985. (authors)

  18. Preconcentration NAA for simultaneous multielemental determination in water sample

    International Nuclear Information System (INIS)

    Chatt, A.

    1999-01-01

    Full text: Environment concerns with water, air, land and their interrelationship viz., human beings, fauna and flora. One of the important environmental compartments is water. Elements present in water might face a whole lot of physico-chemical conditions. This poses challenges to measure their total concentrations as well as different species. Preconcentration of the elements present in water samples is a necessary requisites in water analysis. For multi elements concentration measurements, Neutron Activation Analysis (NAA) is one of the preferred analytical techniques due to its sensitivity and selectivity. In this talk preconcentration NAA for multielemental determination in water sample determination will be discussed

  19. Effects of outcropping groundwater from the F- and H-Area seepage basins on the distribution of fish in Four Mile Creek

    International Nuclear Information System (INIS)

    Paller, M.H.; Storey, C.

    1990-10-01

    Four Mile Creek was electrofished during June 26--July 2, 1990 to assess the impacts of outcropping ground water form the F- and H-Area Seepage Basins on fish abundance and distribution. Number of fish species and total catch were comparable at sample stations upstream from and downstream from the outcropping zone in Four Mile Creek. Species number and composition downstream from the outcropping zone in Four Mile Creek were similar to species number and composition in unimpacted portions of Pen Branch, Steel Creek, and Meyers Branch. These findings indicate that seepage basin outcropping was not adversely affecting the Four Mile Creek fish community. 5 refs., 3 figs., 4 tabs

  20. Laboratory Experiments on Steady State Seepage-Induced Landslides Using Slope Models and Sensors

    Directory of Open Access Journals (Sweden)

    Sandra G. Catane

    2011-06-01

    Full Text Available A thorough understanding of the failure initiation process is crucial in the development of physicallybased early warning system for landslides and slope failures. Laboratory-scale slope models were constructed and subjected to instability through simulated groundwater infiltration. This is done by progressively increasing the water level in the upslope tank and allowing water to infiltrate laterally towards the toe of the slope. Physical changes in the slope models were recorded by tilt sensors and video cameras. When the model slope was destabilized, the chronology of events occurred in the following sequence: (1 bulging at the toe, (2 seepage at the toe, (3 initial failure of soil mass, (4 piping, (5 retrogressive failure, (6 formation of tension cracks and (7 major failure of soil mass. Tension cracks, piping and eventual failure are manifestations of differential settlements due to variations in void ratio. Finite element analysis indicates that instability and subsequent failures in the model slope were induced primarily by high hydraulic gradients in the toe area. Seepage, initial deformation and subsequent failures were manifested in the toe area prior to failure, providing a maximum of 36 min lead time. Similar lead times are expected in slopes of the same material as shown in many case studies of dam failure. The potential of having a longer lead time is high for natural slopes made of materials with higher shear strength thus evacuation is possible. The tilt sensors were able to detect the initial changes before visual changes manifested, indicating the importance of instrumental monitoring.

  1. Methods for Determining Organic Matter and Colour in Water

    Directory of Open Access Journals (Sweden)

    Ramunė Albrektienė

    2011-02-01

    Full Text Available The article examines different methods for determining organic matter and colour in water. Most of organic compounds in water have a humic substance. These substances frequently form complexes with iron. Humic matter gives water a yellow-brownish colour. Water filtration through conventional sand filters does not remove colour and organic compounds, and therefore complicated water treatment methods shall be applied. The methods utilized for organic matter determination in water included research on total organic carbon, permanganate index and the bichromate number of UV absorption of 254 nm wave length. The obtained results showed the greatest dependence between water colour and permanganate index. However, UV adsorption could be used for organic matter determination during the operation of a water treatment plant and the start-up of plants as easy and fast methods.Article in Lithuanian

  2. Seepage phenomena on Mars at subzero temperature

    Science.gov (United States)

    Kereszturi, Akos; Möhlmann, Diedrich; Berczi, Szaniszlo; Ganti, Tibor; Horvath, Andras; Kuti, Adrienn; Pocs, Tamas; Sik, Andras; Szathmary, Eors

    At the southern hemisphere of Mars seasonal slope structures emanating from Dark Dune Spots are visible on MGS MOC, and MRO HiRISE images. Based on their analysis two groups of streaks could be identified: diffuse and fan shaped ones forming in an earlier phase of local spring, probably by CO2 gas jets, and confined streaks forming only on steep slopes during a later seasonal phase. The dark color of the streaks may arise from the dark color of the dune grains where surface frost disappeared above them, or caused by the phase change of the water ice to liquid-like water, or even it may be influenced by the solutes of salts in the undercooled interfacial water The second group's morphology (meandering style, ponds at their end), morphometry, and related theoretical modelling suggest they may form by undercooled water that remains in liquid phase in a thin layer around solid grains. We analyzed sequence of images, temperature and topographic data of Russel (54S 12E), Richardson (72S 180E) and an unnamed crater (68S 2E) during southern spring. The dark streaks here show slow motion, with an average speed of meter/day, when the maximal daytime temperature is between 190 and 220 K. Based on thermophysical considerations a thin layer of interfacial water is inevitable on mineral surfaces under the present conditions of Mars. With 10 precipitable micrometer of atmospheric water vapor, liquid phase can be present down about 190 K. Under such conditions dark streaks may form by the movement of grains lubricatred by interfacial water. This possibility have various consequences on chemical, mechanical or even possible astrobiological processes on Mars. Acknowledgment: This work was supported by the ESA ECS-project No. 98004 and the Pro Renovanda Cultura Hungariae Foundation.

  3. Polyelectrolyte determination in drinking water | Majam | Water SA

    African Journals Online (AJOL)

    Chemical contaminants that occur in drinking water are not usually associated with acute health effects when compared to microbial contaminants and are usually given a lower priority. Those that are of concern have cumulative toxic properties such as metals and substances that are carcinogenic. Some of these potentially ...

  4. Relationship between oxygen isotopes in rainfall, cave percolation waters and speleothem calcite at Waitomo, New Zealand

    International Nuclear Information System (INIS)

    Williams, P.W.; Fowler, A.

    2002-01-01

    The relationship between the δ 18 O values of rainfall, vadose percolation water, and speleothem calcite was investigated in a cave at Waitomo. Water samples were obtained approximately monthly for two years from a storage rain gauge on the surface and from stored seepage from three stalactites underground. Rain water δ 18 O SMOW values varied considerably throughout the observation period, with a precipitation-weighted mean of -5.3 permille. Seasonal variability was evident, with winter values being more negative than summer values. Cave seepage waters had a mean of about -5 permille and showed very little variability and no discernible annual variation. This is explained by thorough mixing in the soil and subcutaneous zone stores. Given the average cave temperature (12.8 degrees C) and the δ 18 O SMOW value determined for seepage water, the δ 18 O PDB value of calcite that is actively depositing in isotopic equilibrium on speleothems at Waitomo should fall in the range of -4.1 to -4.6 permille. Observed delta-values of modern speleothem calcites overlap the positive end of this range of theoretical values, indicating that some growing speleothems are not in isotopic equilibrium with seepage waters, but are experiencing either evaporation or kinetic fractionation. (author). 32 refs., 8 figs

  5. The role of optimality in characterizing CO2 seepage from geological carbon sequestration sites

    Energy Technology Data Exchange (ETDEWEB)

    Cortis, Andrea; Oldenburg, Curtis M.; Benson, Sally M.

    2008-09-15

    Storage of large amounts of carbon dioxide (CO{sub 2}) in deep geological formations for greenhouse gas mitigation is gaining momentum and moving from its conceptual and testing stages towards widespread application. In this work we explore various optimization strategies for characterizing surface leakage (seepage) using near-surface measurement approaches such as accumulation chambers and eddy covariance towers. Seepage characterization objectives and limitations need to be defined carefully from the outset especially in light of large natural background variations that can mask seepage. The cost and sensitivity of seepage detection are related to four critical length scales pertaining to the size of the: (1) region that needs to be monitored; (2) footprint of the measurement approach, and (3) main seepage zone; and (4) region in which concentrations or fluxes are influenced by seepage. Seepage characterization objectives may include one or all of the tasks of detecting, locating, and quantifying seepage. Each of these tasks has its own optimal strategy. Detecting and locating seepage in a region in which there is no expected or preferred location for seepage nor existing evidence for seepage requires monitoring on a fixed grid, e.g., using eddy covariance towers. The fixed-grid approaches needed to detect seepage are expected to require large numbers of eddy covariance towers for large-scale geologic CO{sub 2} storage. Once seepage has been detected and roughly located, seepage zones and features can be optimally pinpointed through a dynamic search strategy, e.g., employing accumulation chambers and/or soil-gas sampling. Quantification of seepage rates can be done through measurements on a localized fixed grid once the seepage is pinpointed. Background measurements are essential for seepage detection in natural ecosystems. Artificial neural networks are considered as regression models useful for distinguishing natural system behavior from anomalous behavior

  6. Unsteady free surface flow in porous media: One-dimensional model equations including vertical effects and seepage face

    Science.gov (United States)

    Di Nucci, Carmine

    2018-05-01

    This note examines the two-dimensional unsteady isothermal free surface flow of an incompressible fluid in a non-deformable, homogeneous, isotropic, and saturated porous medium (with zero recharge and neglecting capillary effects). Coupling a Boussinesq-type model for nonlinear water waves with Darcy's law, the two-dimensional flow problem is solved using one-dimensional model equations including vertical effects and seepage face. In order to take into account the seepage face development, the system equations (given by the continuity and momentum equations) are completed by an integral relation (deduced from the Cauchy theorem). After testing the model against data sets available in the literature, some numerical simulations, concerning the unsteady flow through a rectangular dam (with an impermeable horizontal bottom), are presented and discussed.

  7. Levee Seepage Detection in the Sacramento-San Joaquin Delta Using Polarimetric SAR

    Science.gov (United States)

    An, K.; Jones, C. E.; Bekaert, D. P.

    2017-12-01

    The Sacramento-San Joaquin Delta's extensive levee system protects over 2,800 km2 of reclaimed lands and serves as the main irrigation and domestic water supply for the state of California. However, ongoing subsidence and disaster threats from floods and earthquakes make the Delta levee system highly vulnerable, endangering water supplies for 23 million California residents and 2.5 million acres of agricultural land. Levee failure in the Delta can cause saltwater intrusion from San Francisco Bay, reducing water quality and curtailing water exports to residents, commercial users, and farmers. To protect the Delta levee system, it is essential to search for signs of seepage in which water is piping through or beneath levees, which can be associated with deformation of the levees themselves. Until now, in-situ monitoring has largely been applied, however, this is a time-consuming and expensive approach. We use data acquired with NASA's UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) airborne radar instrument to identify and characterize levee seepages and associated land subsidence through advanced remote sensing technologies. The high spatial resolution of UAVSAR can help to direct surveys to areas that are likely to be experiencing damage. UAVSAR is an L-band airborne sensor with high signal-to-noise ratio, repeat flight track accuracy, and spatial resolution of 7x7 m2 (for multi-looked products) that is necessary for detailed levee monitoring. The adaptability of radar instruments in their ability to see through smoke, haze, and clouds during the day or night, is especially relevant during disaster events, when cloud cover or lack of solar illumination inhibits traditional visual surveys of damage. We demonstrate the advantages of combining polarimetric radar imagery with geographic information systems (GIS) datasets in locating seepage features along critical levee infrastructure in the Delta for 2009-2016. The ability to efficiently locate potential

  8. Mud extrusion and ring-fault gas seepage - upward branching fluid discharge at a deep-sea mud volcano.

    Science.gov (United States)

    Loher, M; Pape, T; Marcon, Y; Römer, M; Wintersteller, P; Praeg, D; Torres, M; Sahling, H; Bohrmann, G

    2018-04-19

    Submarine mud volcanoes release sediments and gas-rich fluids at the seafloor via deeply-rooted plumbing systems that remain poorly understood. Here the functioning of Venere mud volcano, on the Calabrian accretionary prism in ~1,600 m water depth is investigated, based on multi-parameter hydroacoustic and visual seafloor data obtained using ship-borne methods, ROVs, and AUVs. Two seepage domains are recognized: mud breccia extrusion from a summit, and hydrocarbon venting from peripheral sites, hosting chemosynthetic ecosystems and authigenic carbonates indicative of long-term seepage. Pore fluids in freshly extruded mud breccia (up to 13 °C warmer than background sediments) contained methane concentrations exceeding saturation by 2.7 times and chloride concentrations up to five times lower than ambient seawater. Gas analyses indicate an underlying thermogenic hydrocarbon source with potential admixture of microbial methane during migration along ring faults to the peripheral sites. The gas and pore water analyses point to fluids sourced deep (>3 km) below Venere mud volcano. An upward-branching plumbing system is proposed to account for co-existing mud breccia extrusion and gas seepage via multiple surface vents that influence the distribution of seafloor ecosystems. This model of mud volcanism implies that methane-rich fluids may be released during prolonged phases of moderate activity.

  9. Determination of water content in natural zeolites by reflection method

    International Nuclear Information System (INIS)

    Sarria, Lopez P.; Desdin Garcia, V.; Freixas Lemus, V.; Dominguez Ley, O.; Csikai, G.

    1989-01-01

    Water content in natural zeolites collected from different site places in Cuba has been determined by neutron reflection method. Results show that it is possible to separate the minerals abundant in zeolite from the surrounding barren rocks. Water content of about 10% can be determined with 2-3% relative accuracy for different matrices, using 10 m measuring time

  10. Numerical simulations of seepage flow in rough single rock fractures

    Directory of Open Access Journals (Sweden)

    Qingang Zhang

    2015-09-01

    Full Text Available To investigate the relationship between the structural characteristics and seepage flow behavior of rough single rock fractures, a set of single fracture physical models were produced using the Weierstrass–Mandelbrot functions to test the seepage flow performance. Six single fractures, with various surface roughnesses characterized by fractal dimensions, were built using COMSOL multiphysics software. The fluid flow behavior through the rough fractures and the influences of the rough surfaces on the fluid flow behavior was then monitored. The numerical simulation indicates that there is a linear relationship between the average flow velocity over the entire flow path and the fractal dimension of the rough surface. It is shown that there is good a agreement between the numerical results and the experimental data in terms of the properties of the fluid flowing through the rough single rock fractures.

  11. Fluorometric determination of uranium in natural waters

    International Nuclear Information System (INIS)

    Hues, A.D.; Henicksman, A.L.; Ashley, W.H.; Romero, D.

    1977-03-01

    Duplicate 200-μl aliquots of the water samples, as received, are transferred by means of Eppendorf pipettors onto 0.4-g pellets of 2 percent LiF-98 percent NaF flux, contained in platinum dishes. The pellets are dried under heat lamps; then fused over special propane burners. The fused pellets are transferred to a Galvanek-Morrison fluorometer, where they are excited with ultraviolet radiation and the fluorescence is measured. The uranium is calculated by comparing the measured fluorescence with that of other pellets, carried through the same procedure, which contain aliquots of standard uranium solutions. The sensitivity of the method is about 0.2 ppB of uranium, and the precision is approximately 15 relative percent in the 0.2- to 10-ppB uranium concentration range

  12. Estimating the Determinants of Residential Water Demand in Italy

    OpenAIRE

    Giulia Romano; Nicola Salvati; Andrea Guerrini

    2014-01-01

    The aim of this study was to estimate the determinants of residential water demand for chief towns of every Italian province, in the period 2007–2009, using the linear mixed-effects model estimated with the restricted-maximum-likelihood method. Results confirmed that the applied tariff had a negative effect on residential water consumption and that it was a relevant driver of domestic water consumption. Moreover, income per capita had a positive effect on water consumption. Among measured cli...

  13. Radionuclide inventories for the F- and H-area seepage basin groundwater plumes

    Energy Technology Data Exchange (ETDEWEB)

    Hiergesell, Robert A [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Kubilius, Walter P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-05-01

    Within the General Separations Areas (GSA) at the Savannah River Site (SRS), significant inventories of radionuclides exist within two major groundwater contamination plumes that are emanating from the F- and H-Area seepage basins. These radionuclides are moving slowly with groundwater migration, albeit more slowly due to interaction with the soil and aquifer matrix material. The purpose of this investigation is to quantify the activity of radionuclides associated with the pore water component of the groundwater plumes. The scope of this effort included evaluation of all groundwater sample analyses obtained from the wells that have been established by the Environmental Compliance & Area Completion Projects (EC&ACP) Department at SRS to monitor groundwater contamination emanating from the F- and H-Area Seepage Basins. Using this data, generalized groundwater plume maps for the radionuclides that occur in elevated concentrations (Am-241, Cm-243/244, Cs-137, I-129, Ni-63, Ra-226/228, Sr-90, Tc-99, U-233/234, U-235 and U-238) were generated and utilized to calculate both the volume of contaminated groundwater and the representative concentration of each radionuclide associated with different plume concentration zones.

  14. Methane seepage intensities traced by biomarker patterns in authigenic carbonates from the South China Sea

    Science.gov (United States)

    Guan, H.; Feng, D.

    2015-12-01

    Authigenic carbonate rocks from an active seep (Site F) at 1120 m water depth of the South China Sea (SCS) were studied using mineralogical and lipid biomarker analyses. Carbonate mineral compositions, in specific samples, were predominantly aragonite, high-Mg calcite (HMC), or a mixture of both. Abundant 13C-depleted lipid biomarkers (various isoprenoids) diagnostic for archaea provide evidence that anaerobic oxidation of methane (AOM) mediated by anaerobic methane oxidizing archaea (ANME) and their bacterial partners is the major process leading to formation of the carbonates. Nearly a pure suite of AOM biomarkers was preserved in aragonitic carbonate in which predominant consortia were most likely ANME-2/Desulfosarcina & Desulfococcus (DSS) assemblages and a mixture of ANME-2/DSS and ANME-1/DSS consortia in the mixed mineral sample, the predominant consortia are in good accordance with the point that the relative higher methane seepage intensity favors the precipitation of aragonite over HMC. In contrast, the completely different biomarker patterns in HMC sample were mainly composed terrestrial organic matter and marine Thaumarchaea, which most likely originally within sediments accompanied with high organic matter input and low methane supply. This environment is known to be favored for archaea of ANME-1 and precipitation of HMC. High concentrations of 13C-depleted hopanoids, including diplopterol, hopanoic acids and hopanols were observed in the aragonite sample that may be sourced by the intermittent presence of oxic conditions in an overall anoxic condition, which was possibly induced by changing seepage intensities.

  15. The influence of environmental factors and dredging on chironomid larval diversity in urban drainage systems in polders strongly influenced by seepage from large rivers

    DEFF Research Database (Denmark)

    Vermonden, K.; Brodersen, Klaus Peter; Jacobsen, Dean

    2011-01-01

    , in urban waters strongly influenced by seepage of large rivers. Chironomid assemblages were studied in urban surface-water systems (man-made drainage ditches) in polder areas along lowland reaches of the rivers Rhine-Meuse in The Netherlands. Multivariate analysis was used to identify the key environmental...... factors. Taxon richness, Shannon index (H'), rareness of species, and life-history strategies at urban locations were compared with available data from similar man-made water bodies in rural areas, and the effectiveness of dredging for restoring chironomid diversity in urban waters was tested. Three...... diversity of chironomid communities in urban waters affected by nutrient-rich seepage or inlet of river water...

  16. On the determination of the mean excitation energy of water

    DEFF Research Database (Denmark)

    Sabin, John R.; Oddershede, Jens; Sauer, Stephan P. A.

    2013-01-01

    Water is a ubiquitous substance in nature, and thus the mean excitation energy of water is an important quantity for understanding and prediction of the details of many fast ion/molecule collision processes such as those involved in external beam radiotherapy of tumors. There are several methods...... for determining numerical values for a mean excitation energy for water, both theoretical and experimental. Here the factors affecting the determination of the value of the mean excitation energy of water, especially from experiment, are discussed....

  17. SQUIRT, Seepage in Reactor Tube Cracks

    International Nuclear Information System (INIS)

    Paul, D.; Ghadiali, N.; Wilkowski, G.; Rahman, S.; Krishnaswamy, P.

    1997-01-01

    1 - Description of program or function: The SQUIRT software is designed to perform leakage rate and area of crack opening calculations for through-wall cracks in pipes. The fluid in the piping system is assumed to be water at either subcooled or saturated conditions. The development of the SQUIRT computer model enables licensing authorities and industry users to conduct the leak-rate evaluations for leak-before-break applications in a more efficient manner. 2 - Method of solution: The SQUIRT program uses a modified form of the Henry-Fauske model for the thermal-hydraulics analysis together with Elastic-Plastic Fracture Mechanics using GE/EPRI and LBB.ENG2 methods for crack opening analysis. 3 - Restrictions on the complexity of the problem: Squirt requires 512 KB of conventional memory and an organized structure. Software can only be executed from the main SQUIRT23 directory where the software was installed

  18. Estimating the Determinants of Residential Water Demand in Italy

    Directory of Open Access Journals (Sweden)

    Giulia Romano

    2014-09-01

    Full Text Available The aim of this study was to estimate the determinants of residential water demand for chief towns of every Italian province, in the period 2007–2009, using the linear mixed-effects model estimated with the restricted-maximum-likelihood method. Results confirmed that the applied tariff had a negative effect on residential water consumption and that it was a relevant driver of domestic water consumption. Moreover, income per capita had a positive effect on water consumption. Among measured climatic and geographical features, precipitation and altitude exerted a strongly significant negative effect on water consumption, while temperature did not influence water demand. Further, data show that small towns in terms of population served were characterized by lower levels of consumption. Water utilities ownership itself did not have a significant effect on water consumption but tariffs were significantly lower and residential water consumption was higher in towns where the water service was managed by publicly owned water utilities. However, further research is needed to gain a better understanding of the connection between ownership of water utilities and water prices and water consumption.

  19. The methods of cesium-137 determination in sea water

    International Nuclear Information System (INIS)

    Gedeonov, L.I.; Krylov, V.N.; Stepanov, A.V.

    1978-01-01

    New express procedures of Cs-137 determination in sea water using selective sorbents are described. One of them is based on the use of natural radioactive potassium-40 as internal standard. Another one allows to perform Cs-137 determination without use of any standards, by pumping a certain amount of water through several successive identical cells filled with sorbent. The positive feature of the procedures consists in that it is no longer necessary chemical treatment of samples in Cs-133 determination in the sorbent and sea water. The danger of polution of samples by alkali metals which can be introduced with reactive agents in the process of chemical treatment is reduced to minimum

  20. Determinants of virtual water flows in the Mediterranean.

    Science.gov (United States)

    Fracasso, Andrea; Sartori, Martina; Schiavo, Stefano

    2016-02-01

    The aim of the paper is to investigate the main determinants of the bilateral virtual water (water used in the production of a commodity or service) flows associated with international trade in agricultural goods across the Mediterranean basin. We consider the bilateral gross flows of virtual water in the area and study what export-specific and import-specific factors are significantly associated with virtual water flows. We follow a sequential approach. Through a gravity model of trade, we obtain a "refined" version of the variable we aim to explain, one that is free of the amount of flows due to pair-specific factors affecting bilateral trade flows and that fully reflects the impact of country-specific determinants of virtual water trade. A number of country-specific potential explanatory variables, ranging from water endowments to trade barriers, from per capita GDP to irrigation prices, is presented and tested. To identify the variables that help to explain the bilateral flows of virtual water, we adopt a model selection procedure based on model averaging. Our findings confirm one of the main controversial results in the literature: larger water endowments do not necessarily lead to a larger 'export' of virtual water, as one could expect. We also find some evidence that higher water irrigation prices reduce (increase) virtual water 'exports' ('imports'). Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Determination of heavy metals and genotoxicity of water from an ...

    African Journals Online (AJOL)

    Determination of heavy metals and genotoxicity of water from an artesian well ... do Amaral, Vanessa Marques de Oliveira Moraes, Luciana Pereira Silva ... environmental interest because it is the most important zinc producer district of Brazil.

  2. Determining water content and other impurities in Siparuna ...

    African Journals Online (AJOL)

    Aghomotsegin

    2016-03-30

    Mar 30, 2016 ... and thermodynamic parameters, became necessary. (Santos, 2004; Dantas, 2006). ... oil in 80 min distillation (after the first sign of boiling). The essential .... Khankari RK, Law D, Grant DJW (1992). Determination of water ...

  3. Determination of Phenols in Water Samples using a Supported ...

    African Journals Online (AJOL)

    The sample preparation method was tested for the determination of phenols in river water samples and landfill leachate. Concentrations of phenols in river water were found to be in the range 4.2 μg L–1 for 2-chlorophenol to 50 μg L–1 for 4-chlorophenol. In landfill leachate, 4-chlorophenol was detected at a concentration ...

  4. Determining pomegranate water and nitrogen requirements with drip irrigation

    Science.gov (United States)

    Despite being an ancient crop there is limited knowledge on the water and nitrogen (N) requirements of pomegranate. We conducted research at the University of California, Kearney Agricultural Research and Extension Center (KARE) to determine the water and nitrogen requirements of a developing pomegr...

  5. Determination of radium 226 and 228 in water

    International Nuclear Information System (INIS)

    Jeanmaire, L.; Willemot, J.M.; Verry, M.

    1989-01-01

    Usually, only radium 226 is measured in water since determination of radium 228 is not easy at the natural levels. A technique has therefore been developed to measure, at the same time and at low radioactivity levels, two radionuclides most often associated in water and with similar toxicity. Computer data processing brings significant improvements though calculation can be manually done [fr

  6. Calculation of drift seepage for alternative emplacement designs

    International Nuclear Information System (INIS)

    Li, Guomin; Tsang, Chin-Fu; Birkholzer, Jens

    1999-01-01

    The calculations presented in this report are performed to obtain seepage rates into drift and boreholes for two alternative designs of drift and waste emplacement at Yucca Mountain. The two designs are defined according to the Scope of Work 14012021M1, activity 399621, drafted October 6, 1998, and further refined in a conference telephone call on October 13, 1998, between Mark Balady, Jim Blink, Rob Howard and Chin-Fu Tsang. The 2 designs considered are: (1) Design A--Horizontal boreholes 1.0 m in diameter on both sides of the drift, with each borehole 8 m long and inclined to the drift axis by 30 degrees. The pillar between boreholes, measured parallel to the drift axis, is 3.3 m. In the current calculations, a simplified model of an isolated horizontal borehole 8 m long will be simulated. The horizontal borehole will be located in a heterogeneous fracture continuum representing the repository layer. Three different realizations will be taken from the heterogeneous field, representing three different locations in the rock. Seepage for each realization is calculated as a function of the percolation flux. Design B--Vertical boreholes, 1.0 m in diameter and 8.0 m deep, drilled from the bottom of an excavated 8.0 m diameter drift. Again, the drift with the vertical borehole will be assumed to be located in a heterogeneous fracture continuum, representing the rock at the repository horizon. Two realizations are considered, and seepage is calculated for the 8-m drift with and without the vertical 1-m borehole at its bottom

  7. Determination of malachite green and its leuco form in water

    Science.gov (United States)

    Allen, J.L.; Meinertz, J.R.; Gofus, J.E.

    1992-01-01

    Liquid chromatographic (lc) analysis can detect malachite green residues in water at less than 10 mu-g/l. Water samples were concentrated on disposable diol columns, eluted with 0.05m P-toluene-sulfonic acid in methanol, and determined by reversed-phase lc. When combined with a lead oxide postcolumn reactor, the lc method can simultaneously determine both leuco and chromatic forms of malachite green. Recoveries averaged 95.4% For the chromatic form and 57.3% For the leuco form of malachite green oxalate and leuco malachite green in spiked pond water samples. Recoveries of the carbinol form of malachite green (an equilibrium product of the dye in water) from spiked tap water samples averaged 98.6%. Recoveries of leuco malachite green were low and ph-dependent.

  8. Determination of Heavy Metal Levels in Various Industrial Waste Waters

    Directory of Open Access Journals (Sweden)

    Mustafa Şahin Dündar

    2012-06-01

    Full Text Available Important part of the environmetal pollution consists of waste water and water pollution. The water polluted by anthropogenical, industrial, and agricultural originated sources are defined as waste waters which are the main pollution sources for reservoirs, rivers, lakes, and seas. In this work, waste waters of leather, textile, automotive side, and metal plating industries were used to determine the levels of Cu, Zn, Cr, Pb and Ni by using Flame Atomic Absorption Spectrometer. As a result, highest mean levels of copper in supernatants of plating and textile industries were observed as 377,18 ng ml-1, respectively 103 ng ml-1 lead and 963,6 ng ml-1 nickel in plating industry, 1068,2 ng ml-1 zinc and 14557,1 ng ml-1 chromium in plating and leather industries were determined.

  9. Determination of the radioactive concentration of 137Cs in water

    International Nuclear Information System (INIS)

    1986-01-01

    The recently accepted standard method to determine the radioactive concentration of 137 Cs in water is based on the selective retention of cesium ions on ammonium-phosphorous-molybdate followed by the dissolution of the sorbent and the selective precipitation of cesium-hexa-chloro-platinate. The radioactive concentration is determined by the measurement of β disintegration rate of the preparate. (V.N.)

  10. Flame Spectrophotometric Determination of Strontium in Water and Biological Material

    Energy Technology Data Exchange (ETDEWEB)

    Joensson, G

    1964-10-15

    A flame spectrophotometric method has been developed for the determination of strontium in biological material and water samples. Strontium is determined in the presence of calcium at a wavelength of 4607 A. The intensity of the strontium emission from the sample is increased if n-butanol is added to a solution of the sample in water. With a 6 vol% solution of n-butanol in water, an optimum intensity of 3.5 times that obtained with pure water solution is obtained. Anions and alkali metals which might interfere with the flame spectrophotometric determination are separated from the sample by a simple ion exchange operation. The method allows determination of strontium in solutions down to 0.1{mu}g/ml. In this case the standard deviation is 3.1 % and with a strontium concentration of 1 {mu}g/ml the deviation is 0.9 %. This method has been used for the determination of strontium in samples of varying composition such as bone, meat and skin from fishes, samples of human bones, shell-fish, milk, and water, in which case Sr quantities of 5{mu}g were determined with an analytical error of less than 5 % and Sr{sub q}uantities greater than 10 {mu}g with an error of less than 3 %.

  11. Flame Spectrophotometric Determination of Strontium in Water and Biological Material

    International Nuclear Information System (INIS)

    Joensson, G.

    1964-10-01

    A flame spectrophotometric method has been developed for the determination of strontium in biological material and water samples. Strontium is determined in the presence of calcium at a wavelength of 4607 A. The intensity of the strontium emission from the sample is increased if n-butanol is added to a solution of the sample in water. With a 6 vol% solution of n-butanol in water, an optimum intensity of 3.5 times that obtained with pure water solution is obtained. Anions and alkali metals which might interfere with the flame spectrophotometric determination are separated from the sample by a simple ion exchange operation. The method allows determination of strontium in solutions down to 0.1μg/ml. In this case the standard deviation is 3.1 % and with a strontium concentration of 1 μg/ml the deviation is 0.9 %. This method has been used for the determination of strontium in samples of varying composition such as bone, meat and skin from fishes, samples of human bones, shell-fish, milk, and water, in which case Sr quantities of 5μg were determined with an analytical error of less than 5 % and Sr q uantities greater than 10 μg with an error of less than 3 %

  12. Uranium geochemistry in soil and groundwater at the F and H seepage basins

    International Nuclear Information System (INIS)

    Serkiz, S.M.; Johnson, W.H.

    1994-09-01

    For 33 years, low activity liquid wastes from the chemical separation areas at the U.S. Department of Energy's Savannah River Site were disposed of in unlined seepage basins. Soil and associated pore water samples of widely varying groundwater chemistries and contaminant concentrations were collected from the region downgradient of these basins using cone penetrometer technology. Analysis of samples using inductively coupled plasma - mass spectrometry has allowed the investigation of uranium partitioning between the aqueous phase and soil surfaces at this site. The distribution of uranium was examined with respect to the solution and soil chemistry (e.g., pH, redox potential, cation and contaminant concentration) and aqueous-phase chemical speciation modeling. The uranium soil source term at the F- and H-Area Seepage Basins (FHSB) is much smaller than has been used in previous modeling efforts. This should result in a much shorter remediation time and a greater effectiveness of a pump-and-treat design than previously predicted. Distribution coefficients at the (FHSB) were found to vary between 1.2 to 34,000 1 kg -1 for uranium. Differences in sorption of these elements can be explained primarily by changes in aqueous pH and the associated change in soil surface charge. Sorption models were fit directly to sorption isotherms from field samples. All models underestimated the fraction of uranium bound at low aqueous uranium concentrations. Linear models overestimated bound uranium at locations where the aqueous concentration was greater than 500 ppb. Mechanistic models provided a much better estimate of the bound uranium concentrations, especially at high aqueous concentrations. Since a large fraction of the uranium at the site is associated with the low-pH portion of the plume, consideration should be given to pumping water from the lowest pH portions of the plume in the F-Area

  13. Hydrogeology, groundwater seepage, nitrate distribution, and flux at the Raleigh hydrologic research station, Wake County, North Carolina, 2005-2007

    Science.gov (United States)

    McSwain, Kristen Bukowski; Bolich, Richard E.; Chapman, Melinda J.

    2013-01-01

    gradients in the groundwater discharge area near the Neuse River were complex and were affected by fluctuations in river stage, with the exception of a well completed in a diabase dike. Water-quality data from the wells and surface-water sites at the RHRS were collected continuously as well as during periodic sampling events. Surface-water samples collected from a tributary were most similar in chemical composition to groundwater found in the regolith and transition zone. Nitrate (measured as nitrite plus nitrate, as nitrogen) concentrations in the sampled wells and tributary ranged from about 5 to more than 120 milligrams per liter as nitrogen. Waterborne continuous resistivity profiling conducted on the Neuse River in the area of the RHRS measured areas of low apparent resistivity that likely represent groundwater contaminated by high concentrations of nitrate. These areas were located on either side of a diabase dike and at the outfall of two unnamed tributaries. The diabase dike preferentially directed the discharge of groundwater to the Neuse River and may isolate groundwater movement laterally. Discrete temperature measurements made within the pore water beneath the Neuse River revealed seeps of colder groundwater discharging into warmer surface water near a diabase dike. Water-quality samples collected from the pore water beneath the Neuse River indicated that nitrate was present at concentrations as high as 80 milligrams per liter as nitrogen on the RHRS side of the river. The highest concentrations of nitrate were located within pore water collected from an area near a diabase dike that was identified as a suspected seepage area. Hydraulic head was measured and pore water samples were collected from two 140-centimeter-deep (55.1-inch-deep) multiport piezometers that were installed in bed sediments on opposite sides of a diabase dike. The concentration of nitrate in pore water at a suspected seepage area ranged from 42 to 82 milligrams per liter as nitrogen with a

  14. Assessment of produced water contaminated soils to determine remediation requirements

    International Nuclear Information System (INIS)

    Clodfelter, C.

    1995-01-01

    Produced water and drilling fluids can impact the agricultural properties of soil and result in potential regulatory and legal liabilities. Produced water typically is classified as saline or a brine and affects surface soils by increasing the sodium and chloride content. Sources of produced water which can lead to problems include spills from flowlines and tank batteries, permitted surface water discharges and pit areas, particularly the larger pits including reserve pits, emergency pits and saltwater disposal pits. Methods to assess produced water spills include soil sampling with various chemical analyses and surface geophysical methods. A variety of laboratory analytical methods are available for soil assessment which include electrical conductivity, sodium adsorption ratio, cation exchange capacity, exchangeable sodium percent and others. Limiting the list of analytical parameters to reduce cost and still obtain the data necessary to assess the extent of contamination and determine remediation requirements can be difficult. The advantage to using analytical techniques is that often regulatory remediation standards are tied to soil properties determined from laboratory analysis. Surface geophysical techniques can be an inexpensive method to rapidly determine the extent and relative magnitude of saline soils. Data interpretations can also provide an indication of the horizontal as well as the vertical extent of impacted soils. The following discussion focuses on produced water spills on soil and assessment of the impacted soil. Produced water typically contains dissolved hydrocarbons which are not addressed in this discussion

  15. Water balance of an earth fill built of organic clay

    Directory of Open Access Journals (Sweden)

    Birle Emanuel

    2016-01-01

    Full Text Available The paper presents investigations on the water balance of an earth fill built of organic clay in humid climate. As the organic soil used for the fill contains geogenetically elevated concentrations of arsenic, particular attention is paid on the seepage flow through the fill. The test fill is 5 m high, 30 m long and 25 m wide. The fill consists of the organic clay compacted at water contents wet and dry of Proctor Optimum covered by a drainage mat and a 60 cm thick top layer. For the determination of the water balance extensive measuring systems were installed. The seepage at the bottom measured so far was less than 2 % of the precipitation. The interflow in the drainage mat above the compacted organic clay was of similar magnitude. The estimated evapotranspiration reached approx. 84 % of the precipitation. According to these measurements the percolation is much lower than the percolation of many landfill covers in humid climates.

  16. Sorption-scintillation determination of 90Sr in natural water

    International Nuclear Information System (INIS)

    Andryushchenko, A.Yu.; Blank, A.B.; Budakovsky, S.V.; Tarasenko, O.A.; Shevtsov, N.I.

    2003-01-01

    A porous composite material is described for determination of radionuclides in aquatic objects of the environment. Possibilities have been studied for the use of this material in monitoring of 90 Sr content in natural waters. The composite is a scintillator with through pores, the surface of which is impregnated by a sorbent that is selective with respect to strontium. The structure of the material allows combination of two processes--concentrating the radionuclide and measuring its activity. Studies were carried out using both model systems based on reference radioactive solutions and samples of natural water contaminated with radionuclides. It is shown that the use of the proposed method for analysis of natural water allows determination in water of 4x10 -2 Bq l -1 of 90 Sr, which is by two orders of magnitude lower than its maximum acceptable concentration

  17. Neutron fluence determination for light water reactor pressure vessels

    International Nuclear Information System (INIS)

    Gold, R.

    1994-01-01

    A general description of limitations that exist in pressure vessel neutron fluence determinations for commercial light water reactors is presented. Complexity factors that arise in light water reactor pressure vessel neutron fluence calculations are identified and used to analyze calculational limitations. Two broad categories of calculational limitations are introduced, namely benchmark field limitations and deep penetration limitations. Explicit examples of limitations that can arise in each of these two broad categories are presented. These limitations are used to show that the recent draft regulatory guide for the determination of pressure vessel neutron fluence, developed by the Nuclear Regulatory Commission, is based upon procedures and assumptions that are not valid. To eliminate the complexity and limitations of calculational methods, it is recommended that the determination of light water reactor pressure vessel neutron fluence be based upon experiment. Recommendations for improved methods of pressure vessel surveillance neutron dosimetry are advanced

  18. Determination of naturally occurring radionuclides in El-Sin Water

    International Nuclear Information System (INIS)

    Al-Masri, M.S.; Al-Rayyes, A.H.

    2000-01-01

    Naturally occurring radionuclides levels have been determined in El-Sin water for the period of 1995 and 1996. water samples were collected from four sites, which are the main drinking water sources of the area. Radon concentration was found to vary between 0.88 Bq/1 in Lattakia main water supply site and 8.4 Bq/1 in El-Sin springs.The highest values found for other radionuclides were 51.6 mBq/1, 18.6 mB/1 and 24.8 mBq/1 for sup 2 sup 2 sup 6 Ra, sup 2 sup 1 sup 0 Po and total uranium (sup 2 sup 3 sup 4 U and sup 2 sup 3 sup 8 U) respectively. These levels are much lower than the maximum permissible levels in drinking water set by international organization.(author)

  19. Changing composition of microbial communities indicates seepage fluid difference of the Thuwal Seeps in the Red Sea

    KAUST Repository

    Yang, Bo; Zhang, Weipeng; Tian, Renmao; Wang, Yong; Qian, Pei-Yuan

    2015-01-01

    © Springer International Publishing Switzerland 2015. Cold seeps are unique ecosystems that are generally characterized by high salinity and reducing solutions. Seepage fluid, the major water influx of this system, contains hypersaline water, sediment pore water, and other components. The Thuwal cold seeps were recently discovered on the continental margin of the Red Sea. Using 16S rRNA gene pyro-sequencing technology, microbial communities were investigated by comparing samples collected in 2011 and 2013. The results revealed differences in the microbial communities between the two sampling times. In particular, a significantly higher abundance of Marine Group I (MGI) Thaumarchaeota was coupled with lower salinity in 2013. In the brine pool, the dominance of Desulfobacterales in 2011 was supplanted byMGI Thaumarchaeota in 2013, perhaps due to a reduced supply of hydrogen sulfide from the seepage fluid. Collectively, this study revealed a difference in water components in this ecosystem between two sampling times. The results indicated that the seawater in this cold seep displayed a greater number of characteristics of normal seawater in 2013 than in 2011, which might represent the dominant driving force for changes in microbial community structures. This is the first study to provide a temporal comparison of the microbial biodiversity of a cold seep ecosystem in the Red Sea.

  20. Changing composition of microbial communities indicates seepage fluid difference of the Thuwal Seeps in the Red Sea

    KAUST Repository

    Yang, Bo

    2015-06-10

    © Springer International Publishing Switzerland 2015. Cold seeps are unique ecosystems that are generally characterized by high salinity and reducing solutions. Seepage fluid, the major water influx of this system, contains hypersaline water, sediment pore water, and other components. The Thuwal cold seeps were recently discovered on the continental margin of the Red Sea. Using 16S rRNA gene pyro-sequencing technology, microbial communities were investigated by comparing samples collected in 2011 and 2013. The results revealed differences in the microbial communities between the two sampling times. In particular, a significantly higher abundance of Marine Group I (MGI) Thaumarchaeota was coupled with lower salinity in 2013. In the brine pool, the dominance of Desulfobacterales in 2011 was supplanted byMGI Thaumarchaeota in 2013, perhaps due to a reduced supply of hydrogen sulfide from the seepage fluid. Collectively, this study revealed a difference in water components in this ecosystem between two sampling times. The results indicated that the seawater in this cold seep displayed a greater number of characteristics of normal seawater in 2013 than in 2011, which might represent the dominant driving force for changes in microbial community structures. This is the first study to provide a temporal comparison of the microbial biodiversity of a cold seep ecosystem in the Red Sea.

  1. Geochemistry of Natural Gas Seepages in Boto Area, Bancak, Semarang, Central Java

    Directory of Open Access Journals (Sweden)

    Hendra Amijaya

    2017-03-01

    Full Text Available DOI: 10.17014/ijog.4.2.61-70Three seepage gas samples collected from Boto Area, Bancak, Semarang, Central Java, were studied to determine their chemical characteristics using GC and GC-IRMS methods. They are composed 53 - 85% of methane predominantly. However, gas seep Site 3 sample has the highest N2 compound and the lesser extent to the samples Site 2 and Site 1 respectively. The two hydrocarbon gas seeps (Site 1, 2, and Site 3 samples that are characterized by δ13C methane of -35.61‰ and -27.97‰, and values of δD methane of -112‰ and -109‰ respectively, are each isotopically distinct from all others suggesting, at least, they are derived from different maturity level. The Site 3 gas sample is suggested to be more mature than the others.

  2. F/H seepage basin groundwater influent, effluent, precipitated sludge characterization task technical plan

    International Nuclear Information System (INIS)

    Siler, J.L.

    1993-01-01

    A treatability study to support the development of a remediation system which would reduce the contaminant levels in groundwater removed from the aquifers in the vicinity of the F/H seepage basins and southwest of the Mixed Waste Management Facility (MWMF) at the Savannah River facility was conducted. Proposed changes in the remediation system require an additional study to determine whether precipitated sludge generated from the proposed remediation system will be hazardous as defined by RCRA. Several contaminants, such as lead and mercury, are above the groundwater protection standards. The presence of radionuclides and other contaminants in the sludge does not present a problem provided that the sludge can pass the Toxicity Characteristic Leaching Procedure (TCLP) test. The study has been developed in such a manner as to cover the possible range of treatment options that may be used

  3. Cadmium geochemistry in soil and groundwater at the F and H Seepage Basins

    International Nuclear Information System (INIS)

    Serkiz, S.M.; Johnson, W.H.

    1994-10-01

    For 33 years, low activity liquid wastes from the chemical separation areas at the US Department of Energy's Savannah River Site were disposed of in unlined seepage basins. This disposal practice was discontinued in 1988. At that time, the basins were drained and a low permeability cover system was placed over the basins. In the summer of 1993, soil and associated pore water samples of widely varying groundwater chemistries and contaminant concentrations were collected from the region downgradient of these basins using cone penetrometer technology. Analysis of these samples using inductively coupled plasma - mass spectrometry has allowed the investigation of cadmium partitioning between the aqueous phase and soil surfaces at this site. The distribution of cadmium was examined with respect to the solution and soil chemistry and aqueous-phase chemical speciation modeling. Cadmium was detected in 35 of 53 aqueous samples from the F- and H-Area Seepage Basins (FHSB). Porewater concentration were found to vary from 0.48 to 23.5 μg 1 -1 , with a mean concentration of 3.1 ± 4.3 μg 1 -1 . Based on the 43 of 86 soil samples for which cadmium was detected, the concentration in the soil ranged 88.5 to 1090 μg kg -1 . The mean soil concentration was 214 ± 168 μg kg -1 . This concentration is not significantly different from the concentrations observed in two upgradient soil samples collected from the same lithologic unit. The concentrations from these samples were 293 ± 214 and 431 ± 293 μg kg -1

  4. F-Area Seepage Basins groundwater monitoring report -- third and fourth quarters 1993

    International Nuclear Information System (INIS)

    Butler, C.T.

    1994-03-01

    During the second half of 1993, the groundwater at the F-Area Seepage Basins (FASB) was monitored in compliance with Module 3, Section C, of South Carolina Hazardous Waste Permit SC1-890-008-989, effective November 2, 1992. The monitoring well network is composed of 87 FSB wells screened in the three hydrostratigraphic units that make up the uppermost aquifer beneath the FASB. A detailed description of the uppermost aquifer is included in the Resource Conservation and Recovery Act Part B post-closure care permit application for the F-Area Hazardous Waste Management Facility submitted to the South Carolina Department of Health and Environmental Control (SCDHEC) in December 1990. Beginning in the first quarter of 1993, the standard for comparison became the SCDHEC Groundwater Protection Standard (GWPS) specified in the approved F-Area Seepage Basins Part B permit. Currently and historically, gross alpha, nitrate, nonvolatile beta, and tritium are among the primary constituents to exceed standards. Numerous other radionuclides and hazardous constituents also exceeded the GWPS in the groundwater at the FASB during the second half of 1993, notably aluminum, iodine-129, and zinc. The elevated constituents are found primarily in Aquifer Zone 2B 2 and Aquifer Zone 2B 1 wells. However, several Aquifer Unit 2A wells also contain elevated levels of constituents. Isoconcentration/isoactivity maps included in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units. Water-level maps indicate that the groundwater flow rates and directions at the FASB have remained relatively constant since the basins ceased to be active in 1988

  5. A coupling model for gas diffusion and seepage in SRV section of shale gas reservoirs

    Directory of Open Access Journals (Sweden)

    Shusheng Gao

    2017-03-01

    Full Text Available A prerequisite to effective shale gas development is a complicated fracture network generated by extensive and massive fracturing, which is called SRV (stimulated reservoir volume section. Accurate description of gas flow behaviors in such section is fundamental for productivity evaluation and production performance prediction of shale gas wells. The SRV section is composed of bedrocks with varying sizes and fracture networks, which exhibit different flow behaviors – gas diffusion in bedrocks and gas seepage in fractures. According to the porosity and permeability and the adsorption, diffusion and seepage features of bedrocks and fractures in a shale gas reservoir, the material balance equations were built for bedrocks and fractures respectively and the continuity equations of gas diffusion and seepage in the SRV section were derived. For easy calculation, the post-frac bedrock cube was simplified to be a sphere in line with the principle of volume consistency. Under the assumption of quasi-steady flow behavior at the cross section of the sphere, the gas channeling equation was derived based on the Fick's laws of diffusion and the density function of gas in bedrocks and fractures. The continuity equation was coupled with the channeling equation to effectively characterize the complicated gas flow behavior in the SRV section. The study results show that the gas diffusivity in bedrocks and the volume of bedrocks formed by volume fracturing (or the scale of fracturing jointly determines the productivity and stable production period of a shale gas well. As per the actual calculation for the well field A in the Changning–Weiyuan Block in the Sichuan Basin, the matrix has low gas diffusivity – about 10−5 cm2/s and a large volume with an equivalent sphere radius of 6.2 m, hindering the gas channeling from bedrocks to fractures and thereby reducing the productivity of the shale gas well. It is concluded that larger scale of volume fracturing

  6. Evaluation of infiltration for the determination of palms water needs

    Science.gov (United States)

    Benlarbi, Dalila; Boutaoutaou, Djamel; Saggaï, Sofiane

    2018-05-01

    In arid climate conditions, irrigation water requirements increase, but available water resources are limited. And therefore the Saharan regions, large consumers of water can be seriously threatened if they do not make the necessary to become as parsimonious as allow the irrigation techniques whose technological aspect on their improvement has been privileged until now but all the problems are not solved. The objective of this work is to know the process of infiltration of water in the soil, i.e.: to try to determine exactly its value with obtaining the best combination (flow of entry, board length and irrigation time) in order to have a more or less uniform distribution in the soil and especially by avoiding significant water losses that would cause rise in the water table. The infiltration will allow us to calculate at any point the dose of water received that we will compare with the needs of the date palm. For this purpose; we varied the input flow for a constant board length. Then we varied the board length for a constant input rate. In both cases we varied the irrigation time according to the water requirements of the date palm. The flow remains of course constant during the entire feeding period. This study is primarily experimental and aims to meet practical applications but not immediately because it is necessary to continue the experiments with several other combinations to achieve practical results.

  7. Comparative Assessment of Physical and Social Determinants of Water Quantity and Water Quality Concerns

    Science.gov (United States)

    Gunda, T.; Hornberger, G. M.

    2017-12-01

    Concerns over water resources have evolved over time, from physical availability to economic access and recently, to a more comprehensive study of "water security," which is inherently interdisciplinary because a secure water system is influenced by and affects both physical and social components. The concept of water security carries connotations of both an adequate supply of water as well as water that meets certain quality standards. Although the term "water security" has many interpretations in the literature, the research field has not yet developed a synthetic analysis of water security as both a quantity (availability) and quality (contamination) issue. Using qualitative comparative and multi-regression analyses, we evaluate the primary physical and social factors influencing U.S. states' water security from a quantity perspective and from a quality perspective. Water system characteristics are collated from academic and government sources and include access/use, governance, and sociodemographic, and ecosystem metrics. Our analysis indicates differences in variables driving availability and contamination concerns; for example, climate is a more significant determinant in water quantity-based security analyses than in water quality-based security analyses. We will also discuss coevolution of system traits and the merits of constructing a robust water security index based on the relative importance of metrics from our analyses. These insights will improve understanding of the complex interactions between quantity and quality aspects and thus, overall security of water systems.

  8. A model to determine the economic viability of water fluoridation.

    Science.gov (United States)

    Kroon, Jeroen; van Wyk, Philippus Johannes

    2012-01-01

    In view of concerns expressed by South African local authorities the aim of this study was to develop a model to determine whether water fluoridation is economically viable to reduce dental caries in South Africa. Microsoft Excel software was used to develop a model to determine economic viability of water fluoridation for 17 water providers from all nine South African provinces. Input variables for this model relate to chemical cost, labor cost, maintenance cost of infrastructure, opportunity cost, and capital depreciation. The following output variables were calculated to evaluate the cost of water fluoridation: per capita cost per year, cost-effectiveness and cost-benefit. In this model it is assumed that the introduction of community water fluoridation can reduce caries prevalence by an additional 15 percent and that the savings in cost of treatment will be equal to the average fee for a two surface restoration. Water providers included in the study serve 53.5 percent of the total population of South Africa. For all providers combined chemical cost contributes 64.5 percent to the total cost, per capita cost per year was $0.36, cost-effectiveness was calculated as $11.41 and cost-benefit of the implementation of water fluoridation was 0.34. This model confirmed that water fluoridation is an economically viable option to prevent dental caries in South African communities, as well as conclusions over the last 10 years that water fluoridation leads to significant cost savings and remains a cost-effective measure for reducing dental caries, even when the caries-preventive effectiveness is modest. © 2012 American Association of Public Health Dentistry.

  9. Accuracy of the tritium water dilution method for determining water flux in reindeer (Rangifer tarandus)

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, R D; White, R G; Luick, J R

    1976-06-01

    The accuracy of the tritium water dilution method in estimating water flux was evaluated in reindeer under various conditions of temperature and diet. Two non-pregnant female reindeer were restrained in metabolism stalls, within controlled-environment chambers, at temperatures of +10, -5, and -20/sup 0/C; varying amounts of a commercial pelleted ration (crude protein, 13 percent) or mixed lichens (crude protein, 3 percent) were offered, and water was provided ad libitum either as snow or in liquid form. Total body water volume and water turnover were estimated using tritiated water, and the daily outputs of feces and urine were measured for each of 12 different combinations of diet and temperature. Statistical analysis of the data showed that the tritium water dilution technique gives accurate determinations of total body water flux over a wide range of environmental and nutritional conditions.

  10. Modeling of coupled heat transfer and reactive transport processes in porous media: Application to seepage studies at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Mukhopadhyay, Sumit; Sonnenthal, Eric L.; Spycher, Nicolas

    2007-01-01

    When hot radioactive waste is placed in subsurface tunnels, a series of complex changes occurs in the surrounding medium. The water in the pore space of the medium undergoes vaporization and boiling. Subsequently, vapor migrates out of the matrix pore space, moving away from the tunnel through the permeable fracture network. This migration is propelled by buoyancy, by the increased vapor pressure caused by heating and boiling, and through local convection. In cooler regions, the vapor condenses on fracture walls, where it drains through the fracture network. Slow imbibition of water thereafter leads to gradual rewetting of the rock matrix. These thermal and hydrological processes also bring about chemical changes in the medium. Amorphous silica precipitates from boiling and evaporation, and calcite from heating and CO2 volatilization. The precipitation of amorphous silica, and to a much lesser extent calcite, results in long-term permeability reduction. Evaporative concentration also results in the precipitation of gypsum (or anhydrite), halite, fluorite and other salts. These evaporative minerals eventually redissolve after the boiling period is over, however, their precipitation results in a significant temporary decrease in permeability. Reduction of permeability is also associated with changes in fracture capillary characteristics. In short, the coupled thermal-hydrological-chemical (THC) processes dynamically alter the hydrological properties of the rock. A model based on the TOUGHREACT reactive transport software is presented here to investigate the impact of THC processes on flow near an emplacement tunnel at Yucca Mountain, Nevada. We show how transient changes in hydrological properties caused by THC processes often lead to local flow channeling and saturation increases above the tunnel. For models that include only permeability changes to fractures, such local flow channeling may lead to seepage relative to models where THC effects are ignored. However

  11. Modeling of coupled heat transfer and reactive transport processes in porous media: Application to seepage studies at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Mukhopadhyay, S.; Sonnenthal, E.L.; Spycher, N.

    2007-01-01

    When hot radioactive waste is placed in subsurface tunnels, a series of complex changes occurs in the surrounding medium. The water in the pore space of the medium undergoes vaporization and boiling. Subsequently, vapor migrates out of the matrix pore space, moving away from the tunnel through the permeable fracture network. This migration is propelled by buoyancy, by the increased vapor pressure caused by heating and boiling, and through local convection. In cooler regions, the vapor condenses on fracture walls, where it drains through the fracture network. Slow imbibition of water thereafter leads to gradual rewetting of the rock matrix. These thermal and hydrological processes also bring about chemical changes in the medium. Amorphous silica precipitates from boiling and evaporation, and calcite from heating and CO 2 volatilization. The precipitation of amorphous silica, and to a much lesser extent calcite, results in long-term permeability reduction. Evaporative concentration also results in the precipitation of gypsum (or anhydrite), halite, fluorite and other salts. These evaporative minerals eventually redissolve after the boiling period is over, however, their precipitation results in a significant temporary decrease in permeability. Reduction of permeability is also associated with changes in fracture capillary characteristics. In short, the coupled thermal-hydrological-chemical (THC) processes dynamically alter the hydrological properties of the rock. A model based on the TOUGHREACT reactive transport software is presented here to investigate the impact of THC processes on flow near an emplacement tunnel at Yucca Mountain, Nevada. We show how transient changes in hydrological properties caused by THC processes often lead to local flow channeling and saturation increases above the tunnel. For models that include only permeability changes to fractures, such local flow channeling may lead to seepage relative to models where THC effects are ignored. However

  12. Determination of radium-226 in fresh water, using alpha spectroscopy

    International Nuclear Information System (INIS)

    Byrakdar, M. E.

    2006-12-01

    Four radium isotopes are present in nature, i.e. Ra-223, Ra-224, Ra-226, and Ra-228. The first three are alpha emitters while the last is a beta emitter. Because of the importance of the determination of Alpha isotope emitters in pure water (drinking water), this work focuses on the determination of radium-226 as it has the longest half-life (1600 years, in comparison to 11.4 day, 3.66 days for Ra-223 and Ra-224, respectively) using Alpha spectroscopy. This method has the capability to be applied in sampling fields and low detection limit which in turn makes the analysis of low-level radioactive environmental water samples, with hardness does not exceed 40 French Degree, satisfying for health and environment control programmes. However, counting the samples using Alpha spectroscopy has to be immediate (or within 48 hours). (author)

  13. Quality Determination of Pipe-Borne Water in Sokoto Metropolis ...

    African Journals Online (AJOL)

    The quality of the pipe-borne water supplied to Sokoto metropolis was determined in this study. The total bacterial count was carried out using surface plating method of inoculation. The coliforms were enumerated using multiple tube fermentation technique (Most Probable Number Method). Some physicochemical ...

  14. Determination of the Electronics Charge--Electrolysis of Water Method.

    Science.gov (United States)

    Venkatachar, Arun C.

    1985-01-01

    Presents an alternative method for measuring the electronic charge using data from the electrolysis of acidified distilled water. The process (carried out in a commercially available electrolytic cell) has the advantage of short completion time so that students can determine electron charge and mass in one laboratory period. (DH)

  15. Determination of thiobencarb in water samples by gas ...

    African Journals Online (AJOL)

    Homogeneous liquid-liquid microextraction via flotation assistance (HLLME-FA) coupled with gas chromatography-flame ionization detection (GC-FID) was applied for the extraction and determination of thiobencarb in water samples. In this study, a special extraction cell was designed to facilitate collection of the ...

  16. Fluorescent sensing and determination of mercury (II) ions in water ...

    African Journals Online (AJOL)

    In this study we report on a fluorescent sensing probe based on a naphthyl azo dye modified dibenzo-18-crown-6-ether (DB18C6) for the detection and determination of mercury (II) ions in water. The probe showed high sensitivity and selectivity towards the mercury (II) ion among various alkali, alkaline earth, and transition ...

  17. Determination of lead at nanogram level in water samples by ...

    African Journals Online (AJOL)

    A novel method of chemistry applicable to the determination of trace lead in water samples based on the resonance light scattering (RLS) technique has been developed. In dilute phosphoric acid medium, in the presence of a large excess of I-, Pb(II) can form [PbI4]2-, which further reacts with tetrabutyl ammonium bromide ...

  18. Determination of radionuclides in discharged water from gold ...

    African Journals Online (AJOL)

    The levels of radionuclides concentrations in discharged water from gold processing into the environment of Bogoso (Ghana) were determined using radioanalytical techniques. Radioactivity screening was first carried out to identify physical and chemical processing stages that might be concentrating the radionuclides.

  19. Polymer flooding effect of seepage characteristics of the second tertiary combined model of L oilfield block B

    Directory of Open Access Journals (Sweden)

    Huan ZHAO

    2015-06-01

    Full Text Available The second tertiary combined model is applied to develop the second and third type reservoirs which have more oil layer quantity and strong anisotropism, compared to the regular main reservoir with polymer injection, whose seepage characteristics of polymer-injection-after-water-drive shows a remarkable difference, in addition. This development appears to have a larger effect on the remaining oil development and production. Simulating the second tertiary combined model by reservoir numerical simulation under different polymer molecular weight, polymer concentration, polymer injection rate on the polymer injection period, conclusions of the influenced seepage characteristics of original and added perforated interval pressure and water saturation are drawn. The conclusion shows that the polymer molecular weight could influence water saturation of added perforated interval; polymer concentration makes a significant impact on reservoir pressure; polymer injection rate has a great influence on the separate rate of original and added perforated interval. This research provides firm science evidence to the theory of the second tertiary combined model to develop and enhance oil injection-production rate.

  20. Mercury determination in natural waters using neutron activation analysis

    International Nuclear Information System (INIS)

    Cagnone, M.; Marques, R.O.

    1994-01-01

    Available as short communication only. An analytical method for quantitative determination of Mercury traces in river and sea water is proposed. The neutron activation method and radiochemical separation of Mercury by developing of C L 4 Hg -2 complex, and their chromatographic separation using anionic exchange resin Dowex 1 X 8 of 400 mesh is used. The quantitative determination is done by gamma spectrometric analysis. The selection limits reached with this method showed that this is an amenable procedure in routine mercury determination in the ppb level, specially useful in the environmental contamination analysis. (author). 3 refs, 2 figs, 1 tab

  1. Development of electrical analogue model for studying seepage flow under hydraulic structures - case study: Sukkur barrage

    International Nuclear Information System (INIS)

    Gabriel, H.F.; Umar, I.A.; Khan, G.D.

    2003-01-01

    For the solution of groundwater problem many types of models are used, but electrical analogue model is preferred due to its close response with its prototype hydrological system. This model is easy to construct and is reusable. In the model voltage is correlated to groundwater head electric current to flow and capacitance to groundwater storage. The analogy of the model is derived based on Kirchhoffs law and Finite difference form of Laplace equation. The network is consisting of square and rectangular meshes. Scaling factor for voltage and resistors are selected. All the equipment needed for assembling the model are prepared. Terminal strips and their connectivity are checked. Calculated resistors with accurate values after cutting and molding are inserted in the terminal strips and desired section is completed. A network of resistors in X and Z direction is used to represent the aquifer. Two stabilized power supply are used to provide the electrical potential. The worst condition is maintained by supplying the maximum head at upstream and dry condition at downstream. After the development of the model conclusion derived shows that the model are in a position to express the groundwater potential for seepage distribution under the floor with high degree of accuracy. Moreover there is a very good proportion between sample and the actual prototype in existence. The actual model when tested by model show very clear results for the sheet pile in relation to floor length to control seepage or uplift pressure caused. The existence design of Sukkur barrage and its overestimation and underestimation with reference to their sheet pile have been specifically determined. (author)

  2. Determination of symmetrical index for 3H in river waters

    International Nuclear Information System (INIS)

    Jankovic, M.; Todorovic, D.; Jankovic, B.; Nikolic, J.; Sarap, N.

    2011-01-01

    The paper presents the results of determining the symmetric index, which describes the magnitude of the tritium content changes with time, for samples of Sava and Danube river waters and Mlaka creek water. The results cover the period from 2003 to 2008. It was shown that the value of the symmetric index is the highest for Mlaka samples, which is in accordance with the fact that in these samples the highest concentration of tritium was found in comparison with samples of the Sava and Danube. [sr

  3. Reduced gas seepages in ophiolitic complexes: Evidences for multiple origins of the H2-CH4-N2 gas mixtures

    Science.gov (United States)

    Vacquand, Christèle; Deville, Eric; Beaumont, Valérie; Guyot, François; Sissmann, Olivier; Pillot, Daniel; Arcilla, Carlo; Prinzhofer, Alain

    2018-02-01

    This paper proposes a comparative study of reduced gas seepages occurring in ultrabasic to basic rocks outcropping in ophiolitic complexes based on the study of seepages from Oman, the Philippines, Turkey and New Caledonia. This study is based on analyses of the gas chemical composition, noble gases contents, stable isotopes of carbon, hydrogen and nitrogen. These seepages are mostly made of mixtures of three main components which are H2, CH4 and N2 in various proportions. The relative contents of the three main gas components show 4 distinct types of gas mixtures (H2-rich, N2-rich, N2-H2-CH4 and H2-CH4). These types are interpreted as reflecting different zones of gas generation within or below the ophiolitic complexes. In the H2-rich type, associated noble gases display signatures close to the value of air. In addition to the atmospheric component, mantle and crustal contributions are present in the N2-rich, N2-H2-CH4 and H2-CH4 types. H2-bearing gases are either associated with ultra-basic (pH 10-12) spring waters or they seep directly in fracture systems from the ophiolitic rocks. In ophiolitic contexts, ultrabasic rocks provide an adequate environment with available Fe2+ and alkaline conditions that favor H2 production. CH4 is produced either directly by reaction of dissolved CO2 with basic-ultrabasic rocks during the serpentinization process or in a second step by H2-CO2 interaction. H2 is present in the gas when no more carbon is available in the system to generate CH4. The N2-rich type is notably associated with relatively high contents of crustal 4He and in this gas type N2 is interpreted as issued mainly from sediments located below the ophiolitic units.

  4. Platform and Environmental Effects on Above- and In-Water Determinations of Water-Leaving Radiances

    Science.gov (United States)

    Hooker, Stanford B.; Morel, Andre; McClain, Charles R. (Technical Monitor)

    2001-01-01

    A comparison of above- and in-water spectral measurements in Case-1 conditions showed the uncertainty in above-water determinations of water-leaving radiances depended on the pointing angle of the above-water instruments with respect to the side of the ship. Two above-water methods were used to create a diagnostic variable to quantify the presence of superstructure reflections which degraded the above-water intracomparisons of water-leaving radiances by 10.9-33.4% (for far-to-near viewing distances, respectively). The primary conclusions of the above- and in-water intercomparison of water-leaving radiances were as follows: a) the SeaWiFS 5% radiometric objective was achieved with the above-water approach, but reliably with only one method and only for about half the data; b) a decrease in water-leaving radiance values was seen in the presence of swell, although, wave crests were radiometrically brighter than the troughs; and c) standard band ratios used in ocean color algorithms remained severely affected, because of the relatively low signal and, thus, proportionally significant contamination at the 555nm wavelength.

  5. Qualitative and quantitative determination of water in airborne particulate matter

    Directory of Open Access Journals (Sweden)

    S. Canepari

    2013-02-01

    Full Text Available This paper describes the optimization and validation of a new simple method for the quantitative determination of water in atmospheric particulate matter (PM. The analyses are performed by using a coulometric Karl-Fisher system equipped with a controlled heating device; different water contributions are separated by the application of an optimized thermal ramp (three heating steps: 50–120 °C, 120–180 °C, 180–250 °C.

    The analytical performance of the method was verified by using standard materials containing 5.55% and 1% by weight of water. The recovery was greater than 95%; the detection limit was about 20 μg. The method was then applied to NIST Reference Materials (NIST1649a, urban particulate matter and to real PM10 samples collected in different geographical areas. In all cases the repeatability was satisfactory (10–15%.

    When analyzing the Reference Material, the separation of four different types of water was obtained. In real PM10 samples the amount of water and its thermal profile differed as a function of the chemical composition of the dust. Mass percentages of 3–4% of water were obtained in most samples, but values up to about 15% were reached in areas where the chemical composition of PM is dominated by secondary inorganic ions and organic matter. High percentages of water were also observed in areas where PM is characterized by the presence of desert dust.

    A possible identification of the quality of water released from the samples was tried by applying the method to some hygroscopic compounds that are likely contained in PM (pure SiO2, Al2O3, ammonium salts, carbohydrates and dicarboxylic acids and by comparing the results with those obtained from field samples.

  6. Zirconium/niobium-95 determined in Hudson River water

    International Nuclear Information System (INIS)

    Linsalata, P.; Cohen, N.

    1982-01-01

    Zirconium 95 and Niobium 95 are the fission products detected in greatest abundance in Hudson River water following the atmospheric testing of a nuclear device in N.W. China in 1980. Water samples, collected continuously and on a 'grab' basis, and processed monthly, have been studied to determine 95 Zr and 95 Nb concentrations, and plotted against collection time. Total precipitation values for each month, averaged over the whole Hudson River are also plotted. Airborne concentration data were obtained from sites in Lower Manhattan and Chester, N.J. A maximum value for 95 Zr in the Hudson River was found for February 1981. Half-time removal of 95 Zr from water was also calculated. (U.K.)

  7. Practical Guidelines for Water Percolation Capacity Determination of the Ground

    Directory of Open Access Journals (Sweden)

    Mihael Brenčič

    2011-06-01

    Full Text Available Determination of water infiltration capacity of ground soils and rocks represents important part of design and construction procedures of the facilities for the infiltration of clean precipitation water. With their help percolation capacity of ground as well as response of the infiltration facilities to the inflowing precipitation water is estimated.Comparing to other in situ hydrogeological tests they can be understood as simple. However, in every day’s practiceseveral problems during their on site application and desk interpretation can arise. Paper represents review of existingpractical engineering procedures during the performance of percolation tests. Procedures are described for the borehole and shaft percolation tests execution and calculation theory for stationary and non‑stationary percolation tests are given. Theory is illustrated with practical exercises. Interpretations of typical departures from theoretical presumptions according to Hvorslev test of non-stationary test are illustrated.

  8. Tree tomato water requirements determined by neutron probe

    International Nuclear Information System (INIS)

    1994-01-01

    The dynamics of water was studied at ''La Tola'', experimental teaching center of the Central University of Ecuador, in a sandy-loan, typic durustoll soil in which trees tomato were growing. All the components of the crop water balance were determined. Real evapotranspiration (ETR) was estimated through the mass balance method, using every 5-10 days a neutron probe to access the volumetric humidity of the soil. The real evapotranspiration was in direct relation with the growth of the crop, reaching its maximum value of 3,8 mm day-1, at vegetative stage. The soil layer supplying most of the water for the consumptive use of the crop was between 0-40 cm being the root activity also greater in that layer

  9. Groundwater and surface-water interactions and impacts of human activities in the Hailiutu catchment, northwest China

    Science.gov (United States)

    Yang, Zhi; Zhou, Yangxiao; Wenninger, Jochen; Uhlenbrook, Stefan; Wang, Xusheng; Wan, Li

    2017-08-01

    The interactions between groundwater and surface water have been significantly affected by human activities in the semi-arid Hailiutu catchment, northwest China. Several methods were used to investigate the spatial and temporal interactions between groundwater and surface water. Isotopic and chemical analyses of water samples determined that groundwater discharges to the Hailiutu River, and mass balance equations were employed to estimate groundwater seepage rates along the river using chemical profiles. The hydrograph separation method was used to estimate temporal variations of groundwater discharges to the river. A numerical groundwater model was constructed to simulate groundwater discharges along the river and to analyze effects of water use in the catchment. The simulated seepage rates along the river compare reasonably well with the seepage estimates derived from a chemical profile in 2012. The impacts of human activities (river-water diversion and groundwater abstraction) on the river discharge were analyzed by calculating the differences between the simulated natural groundwater discharge and the measured river discharge. Water use associated with the Hailiutu River increased from 1986 to 1991, reached its highest level from 1992 to 2000, and decreased from 2001 onwards. The reduction of river discharge might have negative impacts on the riparian ecosystem and the water availability for downstream users. The interactions between groundwater and surface water as well as the consequences of human activities should be taken into account when implementing sustainable water resources management in the Hailiutu catchment.

  10. Quantitative determination and monitoring of water distribution in Aespoe granite

    International Nuclear Information System (INIS)

    Zimmer, U.

    1998-01-01

    To identify possible zones of two-phase-flow and the extension of the excavation disturbed zone, geoelectric measurements are conducted in the ZEDEX- and the DEMO-tunnel. The electric resistivity of a hard rock is usually determined by its water content, its water salinity and its porosity structure. By calibration measurements of the resistivity on rocks with well known water content, a relation between resistivity and water content for Aespoe granite is determined. This relation is used to correlate the in-situ resistivity with the water content of the rock. To determine the in-situ resistivity between the ZEDEX- and the DEMO-tunnel an electrode array of nearly 300 electrodes was installed along the tunnel walls and in one borehole. With a semiautomatic recording unit which is operated by a telephone connection from the GRS-office in Braunschweig/Germany, the resistivity is monitored between and around the tunnels. To correlate the resistivity with the water content, the measured apparent resistivity has to be converted into a resistivity model of the underground. Since many thin water bearing fractures complicate this inversion process, the accuracy and resolution of the different inversion programs are checked before their application to the data. It was found that an acceptable quantitative reconstruction of the resistivity requires the integration of geometric information about the fracture zones into the inversion process. For a rough estimation of the position of possible fracture zones, a simple inversion without any geometric boundary conditions can be used. Since the maximum investigation area is limited along a single tunnel for profile measurements, tomographic measurements were also applied to estimate the resistivity distribution between the ZEDEX- and the DEMO-tunnel. These tomographic measurements have a lower resolution than the profile measurements due to the required large computer power, but result in reconstructions that give an estimate of

  11. Determination of trace metals in natural fresh waters

    International Nuclear Information System (INIS)

    Holm, K.; Borg, H.; Korhonen, M.

    1989-06-01

    The determination method still most widely used is atomic absorption spectrometry with graphite furnace. The natural levels of several elements are however too low to be accurately determined without any preconcentration. Besides, in sea water, the high salt content causes matric effects, which require time consuming separation steps as solvent extraction or ion exchange. The report describes two procedures for preconcentration of fresh water samples, freeze-drying and replicate injections in the furnace, respectively. The procedures are designed to be used on a routine basis. All water samples are collected in polypropylene bottles which are soaked before use in HCl 1+1, rinsed and allowed to stand until use filled with 0.1 M HNO 3 . The samples are preserved by addition of conc. HNO 3 (2 ml/l, sub boiling distilled). In the freeze-drying procedure, the samples are weighed and frozen in the pre-weighed polypropylene sampling bottles and evaporated to about one tenth of the original volume in the vaccum chamber of a freeze dryer. The samples are then weighed again for determination of the concentration factor and alayzed by graphite furnace AAS. When using the other procedure, the water samples are directly injected into the frunace for several times (2-8) before atomization and measurement of the absorption signal. The drying and ashing step is allowed to proceed after every injection. Comparisons of the two procedures have shown good agreement. The advantage of the replicate injection technique is primarily that the concentration factor is more esily controlled and repeated than by the freeze drying procedure. Further, the latter procedure sometimes suffers from precipitates being formed during the evaporation,especially in humic waters rich in iron. (12 figs., 7 tabs., 14 refs.)

  12. Multielement determination in water by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Naeem, A.

    1987-01-01

    INAA technique was applied to a water sample to determine the elemental concentrations. The sample was irradiated with a neutron flux of 1.2x10 12 n cm -2 s -1 for two different decay times, using two coaxial type high-resolution Ge(Li) detectors. The dominant elements determined in the water sample are Ca, Cl, Na, Mg and K present in ppm-level, while Co, I, Mn, Sm, and Sb are present in smaller amounts, approx. on the average 0.01 ppm. Only traces of other elements such as the rare-earths Ag, As, Ba, Cu, Cd, Fe, Sr, W, Zn, seem to be present. (author)

  13. Determination of radium in water by α-counting

    International Nuclear Information System (INIS)

    Zhu Tianxia

    1986-01-01

    An analytical method is developed for the determination of Ra in water by means of alpha-counting after Ra has been coprecipitated first with PbSO 4 and then with BaSO 4 in EDTA-NH 4 OH with a recovery of ∼99%. Lower limit of the determination is 2.7 x 10 -4 Bq/l by the use of instruments having low Ra-background ≤ 1.3 x 10 -5 Bq. The determination takes 5 hours in the case of having known the ratio 226 Ra/ 224 Ra (B value). If the B value is unknown, another determination is necessary after the sample is allowed to decay for at least 40 hours to give the amounts of 226 Ra and 224 Ra

  14. Determination of inorganic ions in natural water by ion chromatography

    International Nuclear Information System (INIS)

    Nazaratul Ashifa Abdullah Salim; Mohd Suhaimi Hamzah; Eewiat Edin Put; Abdul Khalik Wood; Shamsiah Abdul Rahman; Md Suhaimi Elia

    2010-01-01

    Ion chromatography (IC) is a well established methodology for analysis of ionic species. The concentration of ionic species was determined using suppressed IC with conductivity detection. Anion species were determined in a single 15-min run with Na 2 CO 3 and NaHCO 3 eluent. Cation species were analysed by direct injection of 1 ml and isocratic elution with a methanesulfonic acid (MSA) eluent. Natural water were collected from various sources such as rainwater, lake, river and groundwater. Analysis performance of IC system was validated by evaluating the linear regression of calibration curve, recovery of spike sample and quality control sample. (author)

  15. Determination of radionuclides in discharged water from gold ...

    African Journals Online (AJOL)

    Long-lived radionuclides from the Uranium-, Thorium- and Actinium-decay chains in the discharged water into the environment were radiochemically separated and the activity concentrations determined for 238U-series ranged from 3.8 ± 1.5 to 178 ± 19 mBqL-1, 232Th-series ranged from < 2.0 to 47.8 ± 7.3 mBqL-1 and ...

  16. Spectrophotometric determination of thorium using arsenazo III in water

    International Nuclear Information System (INIS)

    Rio, M.A.P. do; Godoy, J.M. de.

    1985-01-01

    A spectrophotometric determination of thorium with arsenazo III (1,8 dihidroxynaphtaline - 3,6 sulfanic acid - 2,7 bis (azo-2) - phenil argonic acid) was carried out aiming to analyse this element in water. In order to eliminate possible interferences, a coprecipitation with lantanium fluoride was used followed by an extration with 0,2 M TTA (tenoil-trifluor - aceton) / Benzen. The results showed a good agreement with the ones obtained by alfa-spectrometry. (Author) [pt

  17. Nuclear equipment to determine soil and water mass attenuation coefficients

    International Nuclear Information System (INIS)

    Zucchi, O.L.A.D.; Nascimento Filho, V.F. do

    1984-01-01

    The feasibility of substituting the monochannel gamma spectrometer, traditionally used in the gamma ray attenuation technique, for a less sophisticated and less expensive system of integral counting is studied. The proposed system can be operated by a non-specialized person. Three detection systems were used in the determination of the mass attenuation coefficients for different types of soil and for water. (M.A.C.) [pt

  18. Spectrochemical method of uranium determination in sea water

    International Nuclear Information System (INIS)

    Koval'chuk, L.I.; Koryukova, V.P.; Andrianov, A.M.

    1979-01-01

    A spectrochemical method of uranium determination in sea water is reported. The method involves the use of hydrated titanium oxide as a concentrator and a substrate for the analysis. The uranium-containing concentrate mixed with carbon powder (1:1) is burned in the alternating current ark (i=15 A) and the spectra are recorded by a diffraction spectrometer. The analytical line of uranium is 2865.14 A. The variation coefficient is 12%

  19. Determination of deuterium in water by a thermometric method

    International Nuclear Information System (INIS)

    Gabicar, J.

    1976-01-01

    A simple and rapid method for the determination of deuterium in water has been developed. The method is based on the change of the thermal effect of the solubility of sodium sulphate in the presence of D 2 O. The procedure is based on the measurement of the temperature of phase transition Na 2 SO 4 . 10 H 2 O reversible Na 2 SO 4 + 10 H 2 O. The sensitivity of the method proposed is comparable with mass spectrometry. (author)

  20. Determining water and nitrogen balances for beneficial management practices using lysimeters at Wagna test site (Austria).

    Science.gov (United States)

    Klammler, Gernot; Fank, Johann

    2014-11-15

    The shallow Murtal aquifer south of Graz, Austria, provides easily withdrawable groundwater, which is supplied as drinking water without any chemical treatment. The aquifer is also used intensively by agriculture. Common agricultural management practices are the main source for diffuse nitrogen leaching and high groundwater nitrate concentrations. To safeguard the coexisting use of these two important resources, lysimeters are operated at the agricultural test site Wagna, Austria, and the influence of two beneficial management practices--low nitrogen input and organic farming--on nitrogen leaching towards groundwater is investigated. The technical lysimeter design as presented here consists of: (1) high-resolution weighing cells, (2) a suction controlled lower boundary condition for sucking off seepage water, thus emulating undisturbed field conditions, (3) comparative soil temperature, water content and matrix potential measurements inside and outside the lysimeter at different depths, (4) an installation of the lysimeters directly into test plots and (5) a removable upper lysimeter ring enabling machinery soil tillage. Our results indicate that oasis effects or fringe effects of the lysimeter cylinder on unsaturated water flow did not occur. Another lysimeter cultivated with lawn is operated for observing grass-reference evapotranspiration, which resulted in good agreement with calculated grass-reference evapotranspiration according to the FAO-Penman-Monteith method. We conclude that lysimeters installed at Wagna test site did not show any fringe effects and, thus, are appropriate tools for measuring water balance elements and nitrogen leaching of arable and grass land at point scale. Furthermore, our results for the period of 2005 to 2011 show that beneficial management practices reduced nitrate leaching and, hence, may allow for a sustainable coexistence of drinking water supply and agriculture in the Murtal aquifer. Copyright © 2014 Elsevier B.V. All rights

  1. Quantitative Determination of Spring Water Quality Parameters via Electronic Tongue

    Directory of Open Access Journals (Sweden)

    Noèlia Carbó

    2017-12-01

    Full Text Available The use of a voltammetric electronic tongue for the quantitative analysis of quality parameters in spring water is proposed here. The electronic voltammetric tongue consisted of a set of four noble electrodes (iridium, rhodium, platinum, and gold housed inside a stainless steel cylinder. These noble metals have a high durability and are not demanding for maintenance, features required for the development of future automated equipment. A pulse voltammetry study was conducted in 83 spring water samples to determine concentrations of nitrate (range: 6.9–115 mg/L, sulfate (32–472 mg/L, fluoride (0.08–0.26 mg/L, chloride (17–190 mg/L, and sodium (11–94 mg/L as well as pH (7.3–7.8. These parameters were also determined by routine analytical methods in spring water samples. A partial least squares (PLS analysis was run to obtain a model to predict these parameter. Orthogonal signal correction (OSC was applied in the preprocessing step. Calibration (67% and validation (33% sets were selected randomly. The electronic tongue showed good predictive power to determine the concentrations of nitrate, sulfate, chloride, and sodium as well as pH and displayed a lower R2 and slope in the validation set for fluoride. Nitrate and fluoride concentrations were estimated with errors lower than 15%, whereas chloride, sulfate, and sodium concentrations as well as pH were estimated with errors below 10%.

  2. Determinants of Nitrous Oxide Emission from Agricultural Drainage Waters

    International Nuclear Information System (INIS)

    Reay, D. S.; Edwards, A. C.; Smith, K. A.

    2004-01-01

    Emissions of the powerful greenhouse gas nitrous oxide (N 2 O) from agricultural drainage waters are poorly quantified and its determinants are not fully understood. Nitrous oxide formation in agricultural soils is known to increase in response to N fertiliser application, but the response of N 2 O in field drainage waters is unknown. This investigation combined an intensive study of the direct flux of N 2 O from the surface of a fertilised barley field with measurement of dissolved N 2 O and nitrate (NO 3 ) concentrations in the same field's drainage waters. Dissolved N 2 O in drainage waters showed a clear response to field N fertilisation, following an identical pattern to direct N 2 O flux from the field surface. The range in N 2 O concentrations between individual field drains sampled on the same day was large, indicating considerable spatial variability exists at the farm scale. A consistent pattern of very rapid outgassing of the dissolved N 2 O in open drainage ditches was accentuated at a weir, where increased turbulence led to a clear drop in dissolved N 2 O concentration. This study underlines the need for carefully planned sampling campaigns wherever whole farm or catchment N 2 O emission budgets are attempted. It adds weight to the argument for the downward revision of the IPCC emission factor (EF 5 -g) for NO 3 in drainage waters

  3. Determinants of nitrous oxide emission from agricultural drainage waters

    International Nuclear Information System (INIS)

    Reay, D. S.; Edwards, A. C.; Smith, K. A.

    2005-01-01

    Emissions of the powerful greenhouse gas nitrous oxide (N 2 O) from agricultural drainage waters are poorly quantified and its determinants are not fully understood. Nitrous oxide formation in agricultural soils is known to increase in response to N fertiliser application, but the response of N 2 O in field drainage waters is unknown. This investigation combined an intensive study of the direct flux of N 2 O from the surface of a fertilised barley field with measurement of dissolved N 2 O and nitrate (NO 3 ) concentrations in the same field's drainage waters. Dissolved N 2 O in drainage waters showed a clear response to field N fertilisation, following an identical pattern to direct N 2 O flux from the field surface. The range in N 2 O concentrations between individual field drains sampled on the same day was large, indicating considerable spatial variability exists at the farm scale. A consistent pattern of very rapid outgassing of the dissolved N 2 O in open drainage ditches was accentuated at a weir, where increased turbulence led to a clear drop in dissolved N 2 O concentration. This study underlines the need for carefully planned sampling campaigns wherever whole farm or catchment N 2 O emission budgets are attempted. It adds weight to the argument for the downward revision of the IPCC emission factor (EF 5 -g) for NO 3 in drainage waters

  4. Determination of uranium in ground water using different analytical techniques

    International Nuclear Information System (INIS)

    Sahu, S.K.; Maity, Sukanta; Bhangare, R.C.; Pandit, G.G.; Sharma, D.N.

    2014-10-01

    The concern over presence of natural radionuclides like uranium in drinking water is growing recently. The contamination of aquifers with radionuclides depends on number of factors. The geology of an area is the most important factor along with anthropogenic activities like mining, coal ash disposal from thermal power plants, use of phosphate fertilizers etc. Whatever may be the source, the presence of uranium in drinking waters is a matter of great concern for public health. Studies show that uranium is a chemo-toxic and nephrotoxic heavy metal. This chemotoxicity affects the kidneys and bones in particular. Seeing the potential health hazards from natural radionuclides in drinking water, many countries worldwide have adopted the guideline activity concentration for drinking water quality recommended by the WHO (2011). For uranium, WHO has set a limit of 30μgL-1 in drinking water. The geological distribution of uranium and its migration in environment is of interest because the element is having environmental and exposure concerns. It is of great interest to use an analytical technique for uranium analysis in water which is highly sensitive especially at trace levels, specific and precise in presence of other naturally occurring major and trace metals and needs small amount of sample. Various analytical methods based on the use of different techniques have been developed in the past for the determination of uranium in the geological samples. The determination of uranium requires high selectivity due to its strong association with other elements. Several trace level wet chemistry analytical techniques have been reported for uranium determination, but most of these involve tedious and pain staking procedures, high detection limits, interferences etc. Each analytical technique has its own merits and demerits. Comparative assessment by different techniques can provide better quality control and assurance. In present study, uranium was analysed in ground water samples

  5. Coupled LBM-DEM Three-phase Simulation on Seepage of CO2 Stored under the Seabed.

    Science.gov (United States)

    Kano, Y.; Sato, T.

    2017-12-01

    Concerning the seepage of CO2 stored in a subsea formation, CO2 bubble/droplet rises to the sea-surface dissolving into the seawater, and the acidification of local seawater will be a problem. Previous research indicated that seepage rate and bubble size significantly affect its behaviour (Kano et al., 2009; Dewar et al., 2013). On the other hand, Kawada's experiments (2014) indicated that grain size affects formation of gas channels and bubbles through granular media. CO2 seepage through marine sediments probably shows similar behaviour. Additionally, such mobilisation and displacement of sand grains by gas migration may also cause capillary fracturing of CO2 in the reservoir and seal. To predict these phenomena, it is necessary to reveal three-phase behaviour of gas-water-sediment grains. We built gas-liquid-solid three-phase flow 3D simulator by coupling LBM-DEM program, and simulation results showed that the mobilisation of sand grain forms gas channels and affects bubble formation compared with that through solid porous media (Kano and Sato, 2017). In this presentation, we will report simulation results on effects of porosity, grain size and gas flow rate on the formation of gas channels and bubble and their comparison with laboratory experimental data. The results indicate that porosity and grain size of sand gravels affect the width of formed gas channels and resulting formed bubble size on the order of supposed seepage rate in the CO2 storage and that in most of experiment's conditions. References: Abe, S., Place, D., Mora, P., 2004. Pure. Appl. Geophys., 161, 2265-2277. (accessed Aug 01, 2017). Dewar, M., Wei, W., McNeil, D., Chen, B., 2013. Marine Pollution Bulletin 73(2), 504-515. Kano, Y., Sato, T., Kita, J., Hirabayashi, S., Tabeta, S., 2009. Int. J. Greenhouse Gas Control, Vol. 3(5), 617-625. Kano, Y. and Sato, T., 2017. In Proceeding of GHGT-13, Lausanne, Switzerland, Nov. 14-18, 2016. Kawada, R. 2014. Graduation thesis. Faculty of Engineering, The

  6. Recent Experimental Advances to Determine (noble) Gases in Waters

    Science.gov (United States)

    Kipfer, R.; Brennwald, M. S.; Huxol, S.; Mächler, L.; Maden, C.; Vogel, N.; Tomonaga, Y.

    2013-12-01

    In aquatic systems noble gases, radon, and bio-geochemically conservative transient trace gases (SF6, CFCs) are frequently applied to determine water residence times and to reconstruct past environmental and climatic conditions. Recent experimental breakthroughs now enable ● to apply the well-established concepts of terrestrial noble gas geochemistry in waters to the minute water amounts stored in sediment pore space and in fluid inclusions (A), ● to determine gas exchange processes on the bio-geochemical relevant time scales of minutes - hours (B), and ● to separate diffusive and advective gas transport in soil air (C). A. Noble-gas analysis in water samples (transport in the pore space and identifying the origin of bio- and geogenic fluids in (un) consolidated sediments [1]. Advanced techniques that combine crushing and sieving speleothem samples in ultra-high-vacuum to a specific grain size allow to separate air and water-bearing fluid inclusions and thus enables noble-gas-based reconstruction of environmental conditions from water masses as small as 1mg [2]. B. The coupling of noble gas analysis with approaches of gas chromatography permits combined analysis of noble gases and other gases species (e.g., SF6, CFCs, O2, N2) from a single water sample. The new method substantially improves ground water dating by SF6 and CFCs as excess air is quantified from the same sample and hence can adequately be corrected for [3]. Portable membrane-inlet mass spectrometers enable the quasi-continuous and real-time analysis of noble gases and other dissolved gases directly in the field, allowing, for instance, quantification of O2 turnover rates on small time scales [4]. C. New technical developments perfect 222Rn analysis in water by the synchronous the determination of the short-lived 220Rn. The combined 220,222Rn analysis sheds light on the emanation behaviour of radon by identifying soil water content to be the crucial control of 220Rn occurrence in the environment

  7. Seepage safety monitoring model for an earth rock dam under influence of high-impact typhoons based on particle swarm optimization algorithm

    Directory of Open Access Journals (Sweden)

    Yan Xiang

    2017-01-01

    Full Text Available Extreme hydrological events induced by typhoons in reservoir areas have presented severe challenges to the safe operation of hydraulic structures. Based on analysis of the seepage characteristics of an earth rock dam, a novel seepage safety monitoring model was constructed in this study. The nonlinear influence processes of the antecedent reservoir water level and rainfall were assumed to follow normal distributions. The particle swarm optimization (PSO algorithm was used to optimize the model parameters so as to raise the fitting accuracy. In addition, a mutation factor was introduced to simulate the sudden increase in the piezometric level induced by short-duration heavy rainfall and the possible historical extreme reservoir water level during a typhoon. In order to verify the efficacy of this model, the earth rock dam of the Siminghu Reservoir was used as an example. The piezometric level at the SW1-2 measuring point during Typhoon Fitow in 2013 was fitted with the present model, and a corresponding theoretical expression was established. Comparison of fitting results of the piezometric level obtained from the present statistical model and traditional statistical model with monitored values during the typhoon shows that the present model has a higher fitting accuracy and can simulate the uprush feature of the seepage pressure during the typhoon perfectly.

  8. Lead isotopes as seepage indicators around a uranium tailings dam

    International Nuclear Information System (INIS)

    Gulson, B.L.; Mizon, K.J.; Korsch, M.J.; Noller, B.N.

    1989-01-01

    Lead isotope ratios and lead concentrations have been measured in water from 26 bores around the Ranger uranium tailings dam, Northern Territory, Australia, and from the dam itself to determine possible migration of lead derived from the radioactive decay of uranium. Lead isotope compositions have also been measured for the particulates retained on selected filters. The concentration of lead in the bore waters is extremely low (usually 206 Pb/ 204 Pb ratio measured in the bore waters differs by more than a factor of 100 from that in the tailings dam and shows no evidence of lead derived from a significant uranium accumulation. It may be possible to distinguish between lead from the tailings dam and that derived from a nearby uranium ore body

  9. ANALYSIS OF FACTORS CAUSING WATER DAMAGE TO LOESS DOUBLE-ARCHED TUNNEL BASED ON TFN-AHP

    Directory of Open Access Journals (Sweden)

    Mao Zheng-jun

    2017-04-01

    Full Text Available In order to analysis the factors causing water damage to loess double-arched tunnel, this paper conducts field investigation on water damage to tunnels on Lishi-Jundu Expressway in Shanxi, China, confirms its development characteristics, builds an index system (covering 36 evaluation indexes for construction condition, design stage, construction stage, and operation stage for the factors causing water damage to loess double-arched tunnel, applies TFN-AHP (triangular fuzzy number-analytic hierarchy process in calculating the weight of indexes at different levels, and obtains the final sequence of weight of the factors causing water seepage to loess double-arched tunnel. It is found out that water damage to loess double-arched tunnel always develops in construction joints, expansion joints, settlement joints, and lining joints of tunnel and even around them; there is dotted water seepage, linear water seepage, and planar water seepage according to the trace and scope of water damage to tunnel lining. The result shows that water damage to loess double-arched tunnel mainly refers to linear water seepage, planar water seepage is also developed well, and partition and equipment box at the entrance and exit of tunnel are prone to water seepage; construction stage is crucial for controlling water damage to loess double-arched tunnel, atmospheric precipitation is the main water source, and the structure defect of double-arched tunnel increases the possibility of water seepage; the final sequence for weight of various factors is similar to the actual result.

  10. The water kefir grain inoculum determines the characteristics of the resulting water kefir fermentation process.

    Science.gov (United States)

    Laureys, D; De Vuyst, L

    2017-03-01

    To investigate the influence of the water kefir grain inoculum on the characteristics of the water kefir fermentation process. Three water kefir fermentation processes were started with different water kefir grain inocula and followed as a function of time regarding microbial species diversity, community dynamics, substrate consumption profile and metabolite production course. The inoculum determined the water kefir grain growth, the viable counts on the grains, the time until total carbohydrate exhaustion, the final metabolite concentrations and the microbial species diversity. There were always 2-10 lactic acid bacterial cells for every yeast cell and the majority of these micro-organisms was always present on the grains. Lactobacillus paracasei, Lactobacillus hilgardii, Lactobacillus nagelii and Saccharomyces cerevisiae were always present and may be the key micro-organisms during water kefir fermentation. Low water kefir grain growth was associated with small grains with high viable counts of micro-organisms, fast fermentation and low pH values, and was not caused by the absence of exopolysaccharide-producing lactic acid bacteria. The water kefir grain inoculum influences the microbial species diversity and characteristics of the fermentation process. A select group of key micro-organisms was always present during fermentation. This study allows a rational selection of a water kefir grain inoculum. © 2016 The Society for Applied Microbiology.

  11. Electrical resistivity investigation of fluvial geomorphology to evaluate potential seepage conduits to agricultural lands along the San Joaquin River, Merced County, California, 2012–13

    Science.gov (United States)

    Groover, Krishangi D.; Burgess, Matthew K.; Howle, James F.; Phillips, Steven P.

    2017-02-08

    Increased flows in the San Joaquin River, part of the San Joaquin River Restoration Program, are designed to help restore fish populations. However, increased seepage losses could result from these higher restoration flows, which could exacerbate existing drainage problems in neighboring agricultural lands and potentially damage crops. Channel deposits of abandoned river meanders that are hydraulically connected to the river could act as seepage conduits, allowing rapid and widespread water-table rise during restoration flows. There is a need to identify the geometry and properties of these channel deposits to assess their role in potential increased seepage effects and to evaluate management alternatives for reducing seepage. Electrical and electromagnetic surface geophysical methods have provided a reliable proxy for lithology in studies of fluvial and hyporheic systems where a sufficient electrical contrast exists between deposits of differing grain size. In this study, direct-current (DC) resistivity was used to measure subsurface resistivity to identify channel deposits and to map their subsurface geometry. The efficacy of this method was assessed by using DC resistivity surveys collected along a reach of the San Joaquin River in Merced County, California, during the summers of 2012 and 2013, in conjunction with borings and associated measurements from a hydraulic profiling tool. Modeled DC resistivity data corresponded with data from cores, hand-auger samples, a hydraulic profiling tool, and aerial photographs, confirming that DC resistivity is effective for differentiating between silt and sand deposits in this setting. Modeled DC resistivity data provided detailed two-dimensional cross-sectional resistivity profiles to a depth of about 20 meters. The distribution of high-resistivity units in these profiles was used as a proxy for identifying areas of high hydraulic conductivity. These data were used subsequently to guide the location and depth of wells

  12. Variation of stream power with seepage in sand-bed channels

    African Journals Online (AJOL)

    2009-12-27

    Dec 27, 2009 ... Keywords: friction slope, seepage, sediment transport, stream power, suction ... particles from the bed and on further movement of the bed load is of great ..... KNIGHTON AD (1987) River channel adjustment – the down stream.

  13. Distributed optical fiber-based monitoring approach of spatial seepage behavior in dike engineering

    Science.gov (United States)

    Su, Huaizhi; Ou, Bin; Yang, Lifu; Wen, Zhiping

    2018-07-01

    The failure caused by seepage is the most common one in dike engineering. As to the characteristics of seepage in dike, such as longitudinal extension engineering, the randomness, strong concealment and small initial quantity order, by means of distributed fiber temperature sensor system (DTS), adopting an improved optical fiber layer layout scheme, the location of initial interpolation point of the saturation line is obtained. With the barycentric Lagrange interpolation collocation method (BLICM), the infiltrated surface of dike full-section is generated. Combined with linear optical fiber monitoring seepage method, BLICM is applied in an engineering case, which shows that a real-time seepage monitoring technique is presented in full-section of dike based on the combination method.

  14. DETERMINATION OF PHTHALATES FROM BOTTLED WATER BY GC-MS

    Directory of Open Access Journals (Sweden)

    IRINA DUMITRAȘCU

    2012-03-01

    Full Text Available Determination of phthalates from bottled water by GC-MS. Phthalates are ubiquitous pollutants in the environment, due to their widespread use in the last years. These compounds are used principally as plasticizers, to impact flexibility, workability and durability to polymers but they can also be found in products such as paints, adhesives, inks and cosmetics. Phthalates are not chemically bounded to polymers; hence they are easily released and migrate into foods, beverages and drinking water from the packaging or bottling materials or manufacturing processes. This process accelerates as plastic products age and break down. With respect to their endocrine disrupting potential, phthalates such as benzyl butyl phthalate (BBP, di-butyl phthalate (DBP and di-isobutyl phthalate (DIBP have been found to elicit estrogenic responses in in vitro assays. It is possible that phthalates are a contributory factor to endocrine-mediated adverse effects observed in wildlife and humans over the past few decades. In this experiment we have analyzed the phthalates from different bottled waters purchased from the market. Determination by gas chromatography in combination with mass spectrometry detector (GC–MS in electronic ionization mode (EI with selected-ion monitoring (SIM acquisition method (GC–MS (EI–SIM has been carried out. Methods have been developed for both qualitative and quantitative analysis of phthalates. The base peak (m/z = 149 of all the phthalates was selected for the screening studies. The characteristic ions of each compound were chosen for quantitative studies.

  15. Calcareous forest seepages acting as biodiversity hotspots and refugia for woodland snail faunas

    Science.gov (United States)

    Horsák, Michal; Tajovská, Eva; Horsáková, Veronika

    2017-07-01

    Land-snail species richness has repeatedly been found to increase with the increasing site calcium content and humidity. These two factors, reported as the main drivers of land-snail assemblage diversity, are also among the main habitat characteristics of calcareous seepages. Here we explore local species richness and compositional variation of forest spring-fed patches (i.e. seepages), to test the hypothesis that these habitats might act as biodiversity hotspots and refugia of regional snail faunas. In contrast to treeless spring fens, only little is known about land snail faunas inhabiting forest seepages. Studying 25 isolated calcareous forest seepages, evenly distributed across the White Carpathians Protected Landscape Area (SE Czech Republic), we found that these sites, albeit spatially very limited, can harbour up to 66% of the shelled land-snail species known to occur in this well-explored protected area (in total 83 species). By comparing land snail assemblages of the studied seepages with those occurring in the woodland surroundings of each site as well as those previously sampled in 28 preserved forest sites within the study area, we found the seepages to be among the most species rich sites. Although the numbers of species did not statistically differ among these three systems, we found highly significant differences in species composition. Seepage faunas were composed of many species significantly associated with spring sites, in contrast to the assemblages of both surrounding and preserved forest sites. Our results highly support the hypothesis that calcareous forest seepages might serve as refugia and biodiversity hotspots of regional land snail faunas. Protection of these unique habitats challenges both conservation plans and forest management guidelines as they might act as sources for the recolonization and restoration of forest snail assemblages particularly in areas impoverished by harvesting and clearcutting.

  16. Fluoroquinolone antibiotics in environmental waters: sample preparation and determination.

    Science.gov (United States)

    Speltini, Andrea; Sturini, Michela; Maraschi, Federica; Profumo, Antonella

    2010-04-01

    The aim of this review is to provide a general overview on the analytical methods proposed in the last decade for trace fluoroquinolone (FQ) determination in environmental waters. A large number of studies have been developed on this topic in reason of the importance of their monitoring in the studies of environmental mobility and potential degradation pathways. Every step of the analysis has been carefully considered, with a particular attention to sample preparation, in relationship with the problems involved in the analysis of real matrices. The different strategies to minimise interference from organic matter and to achieve optimal sensitivity, especially important in those samples with lower FQ concentrations, were also highlighted. Results and progress in this field have been described and critically commented. Moreover, a worldwide overview on the presence of FQs in the environmental waters has been reported.

  17. Determination of isotopic uranium in food and water

    International Nuclear Information System (INIS)

    Baratta, E.J.; Mackill, P.

    2001-01-01

    The U.S. Food and Drug Administration (FDA) conducts surveys of foods both domestic and imported for the presence of radioactivity. It does not routinely analyze for the actinides, specifically uranium, as it has been shown by previously by studies as reported by WELFORD and others that the concentration in food is very low. This was the result of a 'Tri-City' study. However, at specific sites, the FDA has been requested to analyze for uranium. The concern is that either 'enriched' or 'depleted' uranium has been introduced into the environment and possibly contaminated the food supply. In addition some concern has been raised that water from wells or other sources used for processing food may contain uranium, both natural, depleted or enriched. Methodology for the determination of isotopic uranium, specifically for uranium-238 (depleted) and/or uranium-235 (enriched) in the analyses of food and water samples and the results of these surveys are discussed. (author)

  18. Microwave Determination of Water Mole Fraction in Humid Gas Mixtures

    Science.gov (United States)

    Cuccaro, R.; Gavioso, R. M.; Benedetto, G.; Madonna Ripa, D.; Fernicola, V.; Guianvarc'h, C.

    2012-09-01

    A small volume (65 cm3) gold-plated quasi-spherical microwave resonator has been used to measure the water vapor mole fraction x w of H2O/N2 and H2O/air mixtures. This experimental technique exploits the high precision achievable in the determination of the cavity microwave resonance frequencies and is particularly sensitive to the presence of small concentrations of water vapor as a result of the high polarizability of this substance. The mixtures were prepared using the INRIM standard humidity generator for frost-point temperatures T fp in the range between 241 K and 270 K and a commercial two-pressure humidity generator operated at a dew-point temperature between 272 K and 291 K. The experimental measurements compare favorably with the calculated molar fractions of the mixture supplied by the humidity generators, showing a normalized error lower than 0.8.

  19. Determination of acetone and methyl ethyl ketone in water

    Science.gov (United States)

    Tai, D.Y.

    1978-01-01

    Analytical procedures for the determination of acetone and methyl ethyl ketone in water samples were developed. Concentrations in the milligram-per-liter range were determined by injecting an aqueous sample into the analysis system through an injection port, trapping the organics on Tenax-GC at room temperature, and thermally desorbing the organics into a gas chromatograph with a flame ionization detector for analysis. Concentrations in the microgram-per-liter range were determined by sweeping the headspace vapors over a water sample at 50C, trapping on Tenax-GC, and thermally desorbing the organics into the gas chromatograph. The precision for two operators of the milligram-per-liter concentration procedure, expressed as the coefficient of variation, was generally less than 2 percent for concentrations ranging from 16 to 160 milligrams per liter. The precision from two operators of the microgram-per-liter concentration procedure was between 2 and 4 percent for concentrations of 20 and 60 micrograms per liter. (Woodard-USGS)

  20. Spectrofluorimetric determination of some water-soluble vitamins.

    Science.gov (United States)

    Mohamed, Abdel-Maaboud I; Mohamed, Horria A; Abdel-Latif, Niveen M; Mohamed, Marwa R

    2011-01-01

    Two simple and sensitive spectrofluorimetric methods were developed for determination of three water-soluble vitamins (B1, B2, and B6) in mixtures in the presence of cyanocobalamin. The first one was for thiamine determination, which depends on the oxidation of thiamine HCl to thiochrome by iodine in an alkaline medium. The method was applied accurately to determine thiamine in binary, ternary, and quaternary mixtures with pyridoxine HCl, riboflavin, and cyanocobalamin without interference. In the second method, riboflavin and pyridoxine HCl were determined fluorimetrically in acetate buffer, pH 6. The three water-soluble vitamins (B1, B2, and B6) were determined spectrofluorimetrically in binary, ternary, and quaternary mixtures in the presence of cyanocobalamin. All variables were studied in order to optimize the reaction conditions. Linear relationship was obeyed for all studied vitamins by the proposed methods at their corresponding lambda(exc) or lambda(em). The linear calibration curves were obtained from 10 to 500 ng/mL; the correlation ranged from 0.9991 to 0.9999. The suggested procedures were applied to the analysis of the investigated vitamins in their laboratory-prepared mixtures and pharmaceutical dosage forms from different manufacturers. The RSD range was 0.46-1.02%, which indicates good precision. No interference was observed from common pharmaceutical additives. Good recoveries (97.6 +/- 0.7-101.2 +/- 0.8%) were obtained. Statistical comparison of the results with reported methods shows excellent agreement and indicates no significant difference in accuracy and precision.

  1. Determination of chloride in water. A comparison of three methods

    International Nuclear Information System (INIS)

    Steele, P.J.

    1978-09-01

    The presence of chloride in the water circuits of nuclear reactors, power stations and experimental rigs is undesirable because of the possibility of corrosion. Three methods are considered for the determination of chloride in water in the 0 to 10 μg ml -1 range. The potentiometric method, using a silver-silver chloride electrode, is capable of determining chloride above the 0.1μg ml -1 level, with a standard deviation of 0.03 to 0.12 μg ml -1 in the range 0.1 to 6.0 μg ml -1 chloride. Bromide, iodide and strong reducing agents interfere but none of the cations likely to be present has an effect. The method is very susceptible to variations in temperature. The turbidimetric method involves the production of suspended silver chloride by the addition of silver nitride solution to the sample. The method is somewhat unreliable and is more useful as a rapid, routine limit-testing technique. In the third method, chloride in the sample is pre-concentrated by co-precipitation on lead phosphate, redissolved in acidified ferric nitrate solution and determined colorimetrically by the addition of mercuric thiocyanate solution. It is suitable for determining chloride in the range 0 to 50 μg, using a sample volume of 100 to 500 ml. None of the chemical species likely to be present interferes. In all three methods, chloride contamination can occur at any point in the determination. Analyses should be carried out in conditions where airborne contamination is minimised and a high degree of cleanliness must be maintained. (author)

  2. High purity heavy water production: need for total organic carbon determination in process water streams

    International Nuclear Information System (INIS)

    Ayushi; Kumar, Sangita D.; Reddy, A.V.R.; Vithal, G.K.

    2009-01-01

    In recent times, demand for high purity heavy water (99.98% pure) in industries and laboratories has grown by manifold. Its application started in nuclear industry with the design of CANDU reactor, which uses natural uranium as fuel. In this reactor the purest grade of heavy water is used as the moderator and the primary coolant. Diverse industrial applications like fibre optics, medicine, semiconductors etc. use high purity heavy water extensively to achieve better performance of the specific material. In all these applications there is a stringent requirement that the total organic carbon content (TOC) of high purity heavy water should be very low. This is because the presence of TOC can lead to adverse interactions in different applications. To minimize the TOC content in the final product there is a need to monitor and control the TOC content at each and every stage of heavy water production. Hence a simple, rapid and accurate method was developed for the determination of TOC content in process water samples. The paper summarizes the results obtained for the TOC content in the water samples collected from process streams of heavy water production plant. (author)

  3. Assessing the Impact of Animal Waste Lagoon Seepage on the Geochemistry of an Underlying Shallow Aquifer

    Energy Technology Data Exchange (ETDEWEB)

    McNab, W W; Singleton, M J; Moran, J E; Esser, B K

    2006-03-07

    Dairy facilities and similar confined animal operation settings pose a significant nitrate contamination threat via oxidation of animal wastes and subsequent transport to shallow groundwater. While nitrate contamination resulting from application of animal manure as fertilizer to fields is well recognized, the impact of manure lagoon leakage on groundwater quality is less well characterized. In this study, a dairy facility located in the southern San Joaquin Valley of California has been instrumented with monitoring wells as part of a two-year multidisciplinary study to evaluate nitrate loading and denitrification associated with facility operations. Among multiple types of data collected from the site, groundwater and surface water samples have been analyzed for major cations, anions, pH, oxidation-reduction potential, dissolved organic carbon, and selected dissolved gases (CO{sub 2}, CH{sub 4}, N{sub 2}, Ar, Ne). Modeling of putative geochemical processes occurring within the dairy site manure lagoons shows substantial off-gassing of CO{sub 2} and CH{sub 4} in response to mineralization of organic matter. The gas ebullition appears to strip dissolved gases, including Ar and Ne, from the lagoon water leaving concentrations that are undersaturated with respect to the atmosphere. The resulting fractionated dissolved gas signature serves as an effective tracer for the lagoon water in the underlying shallow groundwater and can be used to constrain inverse geochemical models that assess mixing fractions of lagoon water and local groundwater water. Together with ion exchange and mineral equilibria reactions, identification of lagoon seepage helps explain key attributes of the local groundwater chemistry, including input and cycling of nitrogen, across the site.

  4. F-Area Seepage Basins: Environmental information document

    International Nuclear Information System (INIS)

    Corbo, P.; Killian, T.H.; Kolb, N.L.; Marine, I.W.

    1986-12-01

    This document provides environmental information on postulated closure options for the F-Area Seepage Basins at the Savannah River Plant and was developed as background technical documentation for the Department of Energy's proposed Environmental Impact Statement (EIS) on waste management activities for groundwater protection at the plant. The results of groundwater and atmospheric pathway analyses, accident analysis, and other environmental assessments discussed in this document are based upon a conservative analysis of all foreseeable scenarios as defined by the National Environmental Policy Act (40 CFR 1502.22). The scenarios do not necessarily represent actual environmental conditions. This document is not meant to represent or be used as a regulatory closure plan or other regulatory sufficient document. Technical assistance in the environmental analyses of waste site closures was provided by Clemson University; GeoTrans, Inc.; JBF Associates, Inc.; S.S. Papadopulos and Associates Inc.; Radiological Assessments Corporation; Rogers and Associates Engineering Corporation; Science Applications International Corporation; C.B. Shedrow Environmental Consultants, Inc.; Exploration Software; and Verbatim Typing and Editing

  5. Dose rate determining factors of PWR primary water

    International Nuclear Information System (INIS)

    Terachi, Takumi; Kuge, Toshiharu; Nakano, Nobuo

    2014-01-01

    The relationship between dose rate trends and water chemistry has been studied to clarify the determining factors on the dose rates. Therefore dose rate trends and water chemistry of 11 PWR plants of KEPCO (Kansai Electric Power Co., Inc.) were summarized. It is indicated that the chemical composition of the oxide film, behaviour of corrosion products and Co-58/Co-60 ratio in the primary system have effected dose rate trends based on plant operation experiences for over 40 years. According to plant operation experiences, the amount of Co-58 has been decreasing with the increasing duration of SG (Steam Generator) usage. It is indicated that the stable oxide film formation on the inner surface of SG tubing, is a major beneficial factor for radiation sources reduction. On the other hand, the reduction of the amount of Co-60 for the long term has been not clearly observed especially in particular high dose plants. The primary water parameters imply that considering release and purification balance on Co-59 is important to prevent accumulation of source term in primary water. In addition, the effect of zinc injection, which relates to the chemical composition of oxide film, was also assessed. As the results, the amount of radioactive Co has been clearly decreased. The decreasing trend seems to correlate to the half-life of Co-60, because it is considered that the injected zinc prevents the uptake of radioactive Co into the oxide film on the inner surface of the components and piping. In this paper, the influence of water chemistry and the replacement experiences of materials on the dose rates were discussed. (author)

  6. Determination of Sr-90 in rain water samples

    International Nuclear Information System (INIS)

    Lima, M.F.; Cunha, I.I.L.

    1988-01-01

    A work that aim is to establish radiochemical method for the determination of Sr-90 in rain water samples has been studied, as a step in an environmental monitoring program of radioactive elements. The analysis includes the preconcentration of strontium diluted in a large volume sample by precipitation of strontium as carbonate, separation of strontium from interfering elements (calcium, barium and rare earths), separation of strontium from ytrium, precipitation of purified strontium and ytrium respectively as carbonate and oxalate, and counting of Sr-90 and Y-90 activities in a low background anticoincidence beta counter. (author) [pt

  7. Determination of organic compounds in water using ultraviolet LED

    Science.gov (United States)

    Kim, Chihoon; Ji, Taeksoo; Eom, Joo Beom

    2018-04-01

    This paper describes a method of detecting organic compounds in water using an ultraviolet LED (280 nm) spectroscopy system and a photodetector. The LED spectroscopy system showed a high correlation between the concentration of the prepared potassium hydrogen phthalate and that calculated by multiple linear regression, indicating an adjusted coefficient of determination ranging from 0.953-0.993. In addition, a comparison between the performance of the spectroscopy system and the total organic carbon analyzer indicated that the difference in concentration was small. Based on the close correlation between the spectroscopy and photodetector absorbance values, organic measurement with a photodetector could be configured for monitoring.

  8. Rapid-micro-determination of iodine in water

    International Nuclear Information System (INIS)

    Godin, J.M.; Archimbaud, M.

    1967-03-01

    A method is described for detecting one microgram of iodine per litre of water. After having tested manually volumetric and colorimetric methods, the authors chose a kinetic method. Reduction of arsenious oxide by ceric sulphate is catalyzed by the presence of small quantities of iodine. Failure of manual tests led to the adoption of a Technicon auto-analyzer for carrying out the determination; this improves the reproducibility of the method and gives a sensitivity of about 1 microgram of iodine per litre with an accuracy of ±15 per cent. (authors) [fr

  9. Tests to determine water uptake behaviour of tunnel backfill

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, David (Atomic Energy of Canada Limited (AECL) (Canada)); Anttila, S.; Viitanen, M. (Poeyry InfRa Oy (Finland)); Keto, Paula (Saanio and Riekkola Oy, Helsinki (Finland))

    2008-12-15

    is likely that the backfill can handle somewhat higher inflow rates and provide a longer time period before exiting the backfill. This would provide more capacity to handle interruptions in backfilling operations before remedial actions will be necessary to ensure backfill competence. Based on preliminary data the quantity of material removed by water flowing into and past the backfill in the first 48 hours after inflow begins will range from 0 to 35 g/l. Beyond 48 hours the erosion rate drops to 5 to 15 g per litre of water through-flow. It is flow amount rather than rate that will determine the amount of material removed by water movement along the rock-pellet interfaces. These data provide guidance to the planning and conduct of larger (1/2 scale) tests that will quantify the effects of scale, time, flow path length and flow rate on backfill performance

  10. Tests to determine water uptake behaviour of tunnel backfill

    International Nuclear Information System (INIS)

    Dixon, David; Anttila, S.; Viitanen, M.; Keto, Paula

    2008-12-01

    likely that the backfill can handle somewhat higher inflow rates and provide a longer time period before exiting the backfill. This would provide more capacity to handle interruptions in backfilling operations before remedial actions will be necessary to ensure backfill competence. Based on preliminary data the quantity of material removed by water flowing into and past the backfill in the first 48 hours after inflow begins will range from 0 to 35 g/l. Beyond 48 hours the erosion rate drops to 5 to 15 g per litre of water through-flow. It is flow amount rather than rate that will determine the amount of material removed by water movement along the rock-pellet interfaces. These data provide guidance to the planning and conduct of larger (1/2 scale) tests that will quantify the effects of scale, time, flow path length and flow rate on backfill performance

  11. A method for the determination of technetium in environmental waters

    International Nuclear Information System (INIS)

    Robb, P.; Warwick, P.; Malcolme-Lawes, D.J.

    1985-01-01

    A method is described which can be used to determine technetium-99 levels in a range of water types. Ruthenium isotopes which may interfere in the analysis are removed from the sample by precipitation before concentration of pertechnetate onto an ion-exchange column. Other nuclides can be removed from the column using NaOH before elution of the technetium using NaSCN. The technetium in the NaSNC eluent can then be extracted into butan-2-one which can be evaporated onto a planchette. Technetium-99m is used as a yield tracer and after this has decayed away to negligible levels. The amount of technetium on the planchette can be determined by measuring the rate of beta radiation emission from the final concentrate. (author)

  12. Determination of tributyltin in whole water matrices under the European Water Framework Directive.

    Science.gov (United States)

    Richter, Janine; Fettig, Ina; Philipp, Rosemarie; Jakubowski, Norbert; Panne, Ulrich; Fisicaro, Paola; Alasonati, Enrica

    2016-08-12

    Monitoring of water quality is important to control water pollution. Contamination of the aquatic system has a large effect on human health and the environment. Under the European Water Framework Directive (WFD) 2000/60/EC and the related directive on environmental quality standards (EQS) in the field of water policy 2008/105/EC, the need for sensitive reference methods was highlighted. Since tributyltin (TBT) is one of the WFD listed priority substances a method was developed which is capable to qualify and quantify the pollutant at the required low WFD EQS of 0.2ngL(-1) in whole water bodies, i.e. in non-filtered water samples with dissolved organic carbon and suspended particulate matter. Therefore special attention was paid on the interaction of TBT with the suspended particulate matter and humic substances to obtain a complete representation of the pollution in surface waters. Different water samples were investigated varying the content of organic dissolved and suspended matter. Quantification was performed using species-specific isotope dilution (SSID) and gas chromatography with inductively coupled plasma mass spectrometry (GC-ICP-MS). Different sample treatment strategies were evaluated and compared. The process of internal standard addition was investigated and optimized, hence the equilibrium between internal standards and matrix is of primary importance to perform accurate SSID. Samples spiked at EQS level were analyzed with a recovery between 95 and 105 %. Additionally real surface water samples were investigated and the TBT concentration for the whole water body was determined and compared with conventional routine analysis method. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Spectrophotometric determination of microamounts of boron in water

    International Nuclear Information System (INIS)

    Weber de D'Alessio, Ana; Guido, O.O.; Bandin, N.A.

    1980-01-01

    A fast method of boron in water determination has been studied for the 0.5 .- 2 μg ml -1 concentration range. The procedure is based on the formation of a coloured complex of the tetrafluoroborate of a thionine derivate cation, its extraction by an organic solvent and the further absorptiometric measurement in such media. Methylene blue and azur C were comparatively tested as organic reagents, with 1.2-dichloroethane as the extractant. The absorbance was measured at the maximum (658 nm). The tetrafluoroboric acid formation was reached in 20 min on a water-bath kept at 60 deg C. The sensitivity with methylene blue was higher than with azur C. The molar absorptivities were 65,000 and 38,000 (l mol -1 cm -1 ) respectively. For a boron concentration of 0.1 μg ml -1 the relative standard deviation was 9% for methylene blue and 7% for azur C. The procedure is applicable to the control of boron traces in heavy water of nuclear reactors refrigerating loops. (author) [es

  14. Valley formation by groundwater seepage, pressurized groundwater outbursts and crater-lake overflow in flume experiments with implications for Mars

    Science.gov (United States)

    Marra, Wouter A.; Braat, Lisanne; Baar, Anne W.; Kleinhans, Maarten G.

    2014-04-01

    Remains of fluvial valleys on Mars reveal the former presence of water on the surface. However, the source of water and the hydrological setting is not always clear, especially in types of valleys that are rare on Earth and where we have limited knowledge of the processes involved. We investigated three hydrological scenarios for valley formation on Mars: hydrostatic groundwater seepage, release of pressurized groundwater and crater-lake overflow. Using physical modeling in laboratory experiments and numerical hydrological modeling we quantitatively studied the morphological development and processes involved in channel formation that result from these different sources of water in unconsolidated sediment. Our results show that valleys emerging from seeping groundwater by headward erosion form relatively slowly as fluvial transport takes place in a channel much smaller than the valley. Pressurized groundwater release forms a characteristic source area at the channel head by fluidization processes. This head consist of a pit in case of superlithostatic pressure and may feature small radial channels and collapse features. Valleys emerging from a crater-lake overflow event develop quickly in a run-away process of rim erosion and discharge increase. The valley head at the crater outflow point has a converging fan shape, and the rapid incision of the rim leaves terraces and collapse features. Morphological elements observed in the experiments can help in identifying the formative processes on Mars, when considerations of experimental scaling and lithological characteristics of the martian surface are taken into account. These morphological features might reveal the associated hydrological settings and formative timescales of a valley. An estimate of formative timescale from sediment transport is best based on the final channel dimensions for groundwater seepage valleys and on the valley dimensions for pressurized groundwater release and crater-lake overflow valleys. Our

  15. Delineating a road-salt plume in lakebed sediments using electrical resistivity, piezometers, and seepage meters at Mirror Lake, New Hampshire, U.S.A

    Science.gov (United States)

    Toran, Laura; Johnson, Melanie; Nyquist, Jonathan E.; Rosenberry, Donald O.

    2010-01-01

    Electrical-resistivity surveys, seepage meter measurements, and drive-point piezometers have been used to characterize chloride-enriched groundwater in lakebed sediments of Mirror Lake, New Hampshire, U.S.A. A combination of bottom-cable and floating-cable electrical-resistivity surveys identified a conductive zone (ohm-m)">(ohm-m)(ohm-m) overlying resistive bedrock (ohm-m)">(ohm-m)(ohm-m)beneath the lake. Shallow pore-water samples from piezometers in lakebed sediments have chloride concentrations of 200–1800μeq/liter">200–1800μeq/liter200–1800μeq/liter, and lake water has a chloride concentration of 104μeq/liter">104μeq/liter104μeq/liter. The extent of the plume was estimated and mapped using resistivity and water-sample data. The plume (20×35m">20×35m20×35m wide and at least 3m">3m3m thick) extends nearly the full length and width of a small inlet, overlying the top of a basin formed by the bedrock. It would not have been possible to mapthe plume's shape without the resistivity surveys because wells provided only limited coverage. Seepage meters were installed approximately 40m">40m40m from the mouth of a small stream discharging at the head of the inlet in an area where the resistivity data indicated lake sediments are thin. These meters recorded in-seepage of chloride-enriched groundwater at rates similar to those observed closer to shore, which was unexpected because seepage usually declines away from shore. Although the concentration of road salt in the northeast inlet stream is declining, the plume map and seepage data indicate the groundwater contribution of road salt to the lake is not declining. The findings demonstrate the benefit of combining geophysical and hydrologic data to characterize discharge of a plume beneath Mirror Lake. The extent of the plume in groundwater beneath the lake and stream indicate there will likely be a long-term source of chloride to the lake from groundwater.

  16. Separation and determination of dimethylarsenate in natural waters

    Directory of Open Access Journals (Sweden)

    Ben Issa Nureddin

    2012-01-01

    Full Text Available A simple and efficient method for separation and determination of dimethylarsenate DMAs(V was developed in this work. Two resins, a strong base anion exchange (SBAE resin and iron-oxide coated hybrid (HY resin were tested. By simple adjusting pH value of water at 7.00, DMAs(V passed through the HY column without any changes, while all other arsenic species [inorganic arsenic and monomethylarsonate, MMAs(V] were quantitatively bonded on HY resin. The resin capacity was calculated according to the breakthrough points in a fixed bed flow system. At pH 7.00 the HY resins bonded more than 4150 μg g-1 of As(III, 3500 μg g-1 of As(V and 1500 μg g1 of MMAs(V. Arsenic adsorption behavior in the presence of impurities showed tolerance with the respect to potential interference of anions commonly found in natural water. DMAs(V was determined in the effluent by ICP-MS. The detection limit was 0.03 μg L?1 and relative standard deviation (RSD was between 1.1?7.5 %. Proposed method was established performing standard procedures: with external standard, certified reference material and the standard addition method.

  17. Determination of substraces of alpha emitter elements in water

    International Nuclear Information System (INIS)

    Gascon, J.L.

    1990-01-01

    To determine alpha emitter elements in water by alpha spectrometry, it is necessary to use large volumes of samples, concentration techniq-ues and to separate the elements of interest. In this report a study is presented about two concentration techniques and the process of analysis. Firstly, the stages of concentration method by iron hydroxide coprecipitation were studied in order to improve the results. The combination of liquid-liquid extraction and ion exchange techniques was the best way. Secondly, the technique by adsorption on manganese dioxide was studied. To apply this technique it was necessary to develop analysis methods to separate uranium, thorium, plutonium, americium and radium. These methods were designed combining several techniques of separation: liquid-liquid extraction, liquid-solid extraction, ionic exchange and coprecipitation. After the analysis methods were developped the adsorption on manganese dioxide with artificial samples was studied in the laboratory. Finally, the method of adsorption on manganese dioxide was studied to determine uranium, thorium and radium in the drinking water of Madrid. (Author)

  18. Determination of 210Pb and 210Po in water samples

    International Nuclear Information System (INIS)

    Ayranov, M.; Tosheva, Z.; Kies, A.

    2004-01-01

    Lead-210 and Polonium-210 are naturally occurring members of the Uranium-238 decay series. They could be found in various environmental samples, such as groundwater, fish and shellfish, contributing an important component of the human natural radiation background. For this reason the development of a fast, reproducible and sensitive method for determination of 210 Pb and 210 Po is of a great concern. The aims of our study were to adopt procedures for radiochemical separation of these radionuclides and radioanalytical methods for their determination. The combination of electrochemical deposition, co-precipitation and extraction chromatography gives the opportunity for fast and effective radiochemical separation of the analytes. Polonium was spontaneously plated on copper disk from the stock solution. Lead was co-precipitated with Fe(OH) 3 and further purified by extraction chromatography on Sr Spec columns. Alpha spectra of polonium were collected on Canberra PIPS detectors with 900 mm 2 active surface. The activities of lead were determined by LSC (Gardian Wallac Oy). The minimum detectable activities for sample size 1000 mL and chemical yield of 88 % for the polonium and 85 % for the lead are presented. The proposed method proved to be fast, accurate and reproducible for routine determination of lead and polonium in environmental water samples. (authors)

  19. Heat as a tracer to determine streambed water exchanges

    Science.gov (United States)

    Constantz, J.

    2010-01-01

    This work reviews the use of heat as a tracer of shallow groundwater movement and describes current temperature-based approaches for estimating streambed water exchanges. Four common hydrologic conditions in stream channels are graphically depicted with the expected underlying streambed thermal responses, and techniques are discussed for installing and monitoring temperature and stage equipment for a range of hydrological environments. These techniques are divided into direct-measurement techniques in streams and streambeds, groundwater techniques relying on traditional observation wells, and remote sensing and other large-scale advanced temperatureacquisition techniques. A review of relevant literature suggests researchers often graphically visualize temperature data to enhance conceptual models of heat and water flow in the near-stream environment and to determine site-specific approaches of data analysis. Common visualizations of stream and streambed temperature patterns include thermographs, temperature envelopes, and one-, two-, and three-dimensional temperature contour plots. Heat and water transport governing equations are presented for the case of transport in streambeds, followed by methods of streambed data analysis, including simple heat-pulse arrival time and heat-loss procedures, analytical and time series solutions, and heat and water transport simulation models. A series of applications of these methods are presented for a variety of stream settings ranging from arid to continental climates. Progressive successes to quantify both streambed fluxes and the spatial extent of streambeds indicate heat-tracing tools help define the streambed as a spatially distinct field (analogous to soil science), rather than simply the lower boundary in stream research or an amorphous zone beneath the stream channel.

  20. The determinants of thermal comfort in cool water.

    Science.gov (United States)

    Guéritée, J; House, J R; Redortier, B; Tipton, M J

    2015-10-01

    Water-based activities may result in the loss of thermal comfort (TC). We hypothesized that in cooling water, the hands and feet would be responsible. Supine immersions were conducted in up to five clothing conditions (exposing various regions), as well as investigations to determine if a "reference" skin temperature (Tsk) distribution in thermoneutral air would help interpret our findings. After 10 min in 34.5 °C water, the temperature was decreased to 19.5 °C over 20 min; eight resting or exercising volunteers reported when they no longer felt comfortable and which region was responsible. TC, rectal temperature, and Tsk were measured. Rather than the extremities, the lower back and chest caused the loss of overall TC. At this point, mean (SD) chest Tsk was 3.3 (1.7) °C lower than the reference temperature (P = 0.005), and 3.8 (1.5) °C lower for the back (P = 0.002). Finger Tsk was 3.1 (2.7) °C higher than the reference temperature (P = 0.037). In cool and cooling water, hands and feet, already adapted to colder air temperatures, will not cause discomfort. Contrarily, more discomfort may arise from the chest and lower back, as these regions cool by more than normal. Thus, Tsk distribution in thermoneutral air may help understand variations in TC responses across the body. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Molecular Determinants of Dissolved Organic Matter Reactivity in Lake Water

    Directory of Open Access Journals (Sweden)

    Alina Mostovaya

    2017-12-01

    Full Text Available Lakes in the boreal region have been recognized as the biogeochemical hotspots, yet many questions regarding the regulators of organic matter processing in these systems remain open. Molecular composition can be an important determinant of dissolved organic matter (DOM fate in freshwater systems, but many aspects of this relationship remain unclear due to the complexity of DOM and its interactions in the natural environment. Here, we combine ultrahigh resolution mass spectrometry (FT-ICR-MS with kinetic modeling of decay of >1,300 individual DOM molecular formulae identified by mass spectrometry, to evaluate the role of specific molecular characteristics in decomposition of lake water DOM. Our data is derived from a 4 months microbial decomposition experiment, carried out on water from three Swedish lakes, with the set-up including natural lake water, as well as the lake water pretreated with UV light. The relative decay rate of every molecular formula was estimated by fitting a single exponential model to the change in FT-ICR-MS signal intensities over decomposition time. We found a continuous range of exponential decay coefficients (kexp within different groups of compounds and show that for highly unsaturated and phenolic compounds the distribution of kexp was shifted toward the lowest values. Contrary to this general trend, plant-derived polyphenols and polycondensed aromatics were on average more reactive than compounds with an intermediate aromaticity. The decay rate of aromatic compounds increased with increasing nominal oxidation state of carbon, and molecular mass in some cases showed an inverse relationship with kexp in the UV-manipulated treatment. Further, we observe an increase in formulae-specific kexp as a result of the UV pretreatment. General trends in reactivity identified among major compound groups emphasize the importance of the intrinsic controllers of lake water DOM decay. However, we additionally indicate that each

  2. Removal Site Evaluation Report to the C-Reactor Seepage Basins (904-066, -067 and -068G)

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, E.R. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1997-07-01

    Removal Site Evaluation Reports are prepared in accordance with Section 300.410 of the National Contingency Plan (NCP) and Section X of the Federal Facility Agreement (FFA). The C-Reactor Seepage Basins (904-066G,-067G,-068G) are listed in Appendix C, Resource Conservation and Recovery Act (RCRA)/Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Units List, of the FFA. The purpose of this investigation is to report information concerning conditions at this unit sufficient to assess the threat (if any) posed to human health and the environment and to determine the need for additional CERCLA action. The scope of the investigation included a review of past survey and investigation data, the files, and a visit to the unit.Through this investigation unacceptable conditions of radioactive contaminant uptake in on-site vegetation were identified. This may have resulted in probable contaminant migration and become introduced into the local ecological food chain. As a result, the SRS will initiate a time critical removal action in accordance with Section 300.415 of the NCP and FFA Section XIV to remove, treat (if required), and dispose of contaminated vegetation from the C-Reactor Seepage Basins. Erosion in the affected areas will be managed by an approved erosion control plan. further remediation of this unit will be conducted in accordance with the FFA.

  3. Removal Site Evaluation Report to the C-Reactor Seepage Basins (904-066, -067 and -068G)

    International Nuclear Information System (INIS)

    Palmer, E.R.

    1997-07-01

    Removal Site Evaluation Reports are prepared in accordance with Section 300.410 of the National Contingency Plan (NCP) and Section X of the Federal Facility Agreement (FFA). The C-Reactor Seepage Basins (904-066G,-067G,-068G) are listed in Appendix C, Resource Conservation and Recovery Act (RCRA)/Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Units List, of the FFA. The purpose of this investigation is to report information concerning conditions at this unit sufficient to assess the threat (if any) posed to human health and the environment and to determine the need for additional CERCLA action. The scope of the investigation included a review of past survey and investigation data, the files, and a visit to the unit.Through this investigation unacceptable conditions of radioactive contaminant uptake in on-site vegetation were identified. This may have resulted in probable contaminant migration and become introduced into the local ecological food chain. As a result, the SRS will initiate a time critical removal action in accordance with Section 300.415 of the NCP and FFA Section XIV to remove, treat (if required), and dispose of contaminated vegetation from the C-Reactor Seepage Basins. Erosion in the affected areas will be managed by an approved erosion control plan. further remediation of this unit will be conducted in accordance with the FFA

  4. Spectrophotometric determination of silica in water. Low range; Determinacion espectrofotometrica de silicio en aguas. Rango bajo

    Energy Technology Data Exchange (ETDEWEB)

    Acosta L, E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: eal@nuclear.inin.mx

    1992-07-15

    The spectrophotometric method for the determination of the silica element in water, demineralized water, raw waters, laundry waters, waters treated with ion exchange resins and sea waters is described. This method covers the determination of the silica element in the interval from 20 to 1000 {mu}g/l on 50 ml. of base sample. These limits its can be variable if the size of the used aliquot one is changed for the final determination of the silica element. (Author)

  5. Fault zone controlled seafloor methane seepage in the rupture area of the 2010 Maule Earthquake, Central Chile

    OpenAIRE

    Geersen, Jacob; Scholz, Florian; Linke, Peter; Schmidt, Mark; Lange, Dietrich; Behrmann, Jan H.; Völker, David; Hensen, Christian

    2016-01-01

    Seafloor seepage of hydrocarbon-bearing fluids has been identified in a number of marine forearcs. However, temporal variations in seep activity and the structural and tectonic parameters that control the seepage often remain poorly constrained. Subduction-zone earthquakes for example, are often discussed to trigger seafloor seepage but causal links that go beyond theoretical considerations have not yet been fully established. This is mainly due to the inaccessibility of offshore epicentral a...

  6. Photometric determination of trace cadmium in waste water drained from uranium mining and water-metallurgy

    International Nuclear Information System (INIS)

    Zhu Zihui; Gu Gang; Xu Quanxiu

    1987-09-01

    Cadmium (Cd) ions react with dithizone to form a pink to red color that can be extracted with chloroform and measured photometrically. Dithizone method is one of standard method to determine trace Cd in the environmental waste water. This method, however, can not be suitable for measuring the trace Cd in the waste water drained from uranium mining and water-metallurgy factory, because this kind of waste water contains magnesium ions as high as 1500 mg/L. One more discomfort is that the method needs to use a large amount of potassium cyanide. The authors, therefore, used potassium fluorine as a precipitator that removed the excess magnesium ions in the experimental system, and try to reduce the amount of potassium cyanide to 1/20 of original usage. The experimental results indicated that the modified method as mentioned above was very satisfactory either to simulated samples or to actual samples of waste water drained from uranium mining and water-metallurgy plants. In Summary, this modified method has higher sensitivity with minimun detectable quantity of 0.02 ppm and it is accurate and reproducible with recovery rate of 100 ± 5%

  7. H-Area Seepage Basins: Environmental information document

    International Nuclear Information System (INIS)

    Killian, T.H.; Kolb, N.L.; Corbo, P.

    1986-12-01

    The basins contain liquid low-level radioactivity and chemicals from the H-Area separations facility. Wells monitor the water table in the vicinity of the basins and also underlying aquifers to detect any vertical contaminant migration. A statistical analysis of monitoring data from this site indicates elevated levels of chloride, fluoride, manganese, mercury, nitrate, sodium, and total radium in the groundwater. The predominant pathways for human exposure to contaminants are surface, subsurface, and atmospheric transport. Modeling calculations were performed to determine the risks to humans via these pathways for the postulated closure options. Modeling calculations were also performed to determine ecological impacts. The environmental impact evaluation indicates that the relative human health risks for all closure options are low. Tritium, the dominant radionuclide, reached a maximum risk in Year -29 (from 1985) of 2.7E-04 HE/yr. Results of the atmospheric pathway modeling indicate that risks associated with the no action option are 2 or more orders of magnitude greater than the waste removal closure option for both radionuclides and chemicals. Ecological analysis indicates that the choice of closure option has no effect on the maximum surface water quality impacts. Implementation of no waste removal or waste removal closure options would not appreciably accelerate a decline in groundwater outcrop concentrations. 49 refs., 41 figs., 94 tabs

  8. Investigation of groundwater seepage from the Hanford shoreline of the Columbia River

    International Nuclear Information System (INIS)

    McCormack, W.D.; Carlile, J.M.V.

    1984-11-01

    Groundwater discharges to the Columbia River are evaluated by the Hanford Environmental Surveillance and Groundwater Surveillance Programs via monitoring of the Columbia River and Hanford groundwater. Both programs concluded that Hanford groundwater has not adversely affected Columbia River water quality. This report supplements the above programs by investigating the general characteristics of groundwater entering the Columbia River from the Hanford Site. Specific objectives of the investigation were to identify general shoreline areas where Hanford-related materials were entering the river, and to evaluate qualitatively the physical characteristics and relative magnitudes of those discharges. The study was conducted in two phases. Phase 1 involved visual inspection of Columbia River shoreline, within the Hanford Site, for indications of groundwater seepage. As a result of that inspection, 115 springs suspected of discharging groundwater were recorded. During Phase 2, water samples were collected from these springs and analyzed for Hanford-related materials known to be present in the groundwater. The specific materials used as indicators for the majority of samples were tritium or uranium and nitrate. The magnitude and distribution of concentrations measured in the spring samples were consistent with concentrations of these materials measured in groundwater near the sampled spring locations. Water samples were also collected from the Columbia River to investigate the localized effects of groundwater discharges occurring above and below river level. These samples were collected within 2 to 4 m of the Hanford shoreline and analyzed for tritium, nitrate, and uranium. Elevated concentrations were measured in river samples collected near areas where groundwater and spring concentrations were elevated. All concentrations were below applicable DOE Concentration Guides. 8 references, 6 figures, 7 tables

  9. Determination of metals in water from Billings dam, Sao Paulo

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Talita; Sarkis, Jorge E.S.; Ulrich, Joao C.; Yamaguishi, Renata Bazante, E-mail: taoliveira@ipen.br, E-mail: jesarkis@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Menezes, Luciana Carvalho Bezerra de; Castro, Paula Maria Genova de; Monteiro Junior, Adalberto Jose; Maruyama, Lidia Sumile, E-mail: lcbm@usp.br [Instituto de Pesca, (IP/SAA-SP), Sao Paulo, SP (Brazil). Secretaria da Agricultura e Abastecimento do Estado de Sao Paulo

    2013-07-01

    The Billings reservoir, located in Sao Paulo, Brazil, is used for several purposes such as: water supply, electric generation, fishing and leisure. Although considered an area of environmental protection, in recent years the dam has suffered diverse environmental aggressions including the release of toxic metals. This study presents a recent evaluation of metal contents along the Dam. Samples were collected every three months during the period of winter 2009 to summer 2010. Samples were collected in thirteen points along of the dam, as follows: Rio dos Porcos (Point 1), Summit Control (Point 2), Ilha do Bigua (Point 3), Casa Caida (Point 4), Barragem (Point 5), Foz de Taquacetuba (Point 6), Braco Borore (Point 7), Foz de Borore (Point 8), Alvarenga (Point 9), Pedreira (Point 10), Borore's Margin (Point 11), Capivari I's Margin (Point 12) and Capivari II's Margin (Point 13). The determination of Al, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn was performed by using high resolution inductively coupled plasma mass spectrometer (HR-ICPMS). The methodology has been validated using certified reference material Riverine Water Reference Material for Trace Metals provided by National Research Council Canada (NRCC). The sampling points located in the Pedreira, Borore's Margin, Alvarenga, Barragem Taquacetuba, Casa Caida e Ilha do Bigua presented the highest concentrations. The level for Fe, Cu and Ni were higher than the ones reported in the literature and above the limit set by CONAMA 2914/201. (author)

  10. Micellar electrokinetic chromatographic determination of triazine herbicides in water samples.

    Science.gov (United States)

    Li, Zhi; Zhang, Shuaihua; Yin, Xiaofang; Wang, Chun; Wang, Zhi

    2014-09-01

    Dispersive liquid-liquid microextraction combined with online sweeping preconcentration in micellar electrokinetic chromatography was developed for the simultaneous determination of five triazine herbicides (atrazine, simazine, propazine, prometon and simetryn) in water samples. Several experimental parameters affecting the extraction efficiencies such as the type and volume of both the extraction and dispersive solvents, the addition of salt to sample solution, the extraction time and the pH of the sample solution were investigated. Under optimum conditions, the linearity of the method was good in the range from 0.33 to 20 ng mL(-1) for simazine, propazine, atrazine and simetryn, and from 0.17 to 20 ng mL(-1) for prometon, respectively. The sensitivity enrichment factors were in the range from 1750 to 2100, depending on the compound. The limit of detection (S/N = 3) ranged from 0.05 to 0.10 ng mL(-1). The developed method was successfully applied to the analysis of the five triazines in river, ground and well waters. © The Author [2013]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Determination of metals in water from Billings dam, Sao Paulo

    International Nuclear Information System (INIS)

    Oliveira, Talita; Sarkis, Jorge E.S.; Ulrich, Joao C.; Yamaguishi, Renata Bazante; Menezes, Luciana Carvalho Bezerra de; Castro, Paula Maria Genova de; Monteiro Junior, Adalberto Jose; Maruyama, Lidia Sumile

    2013-01-01

    The Billings reservoir, located in Sao Paulo, Brazil, is used for several purposes such as: water supply, electric generation, fishing and leisure. Although considered an area of environmental protection, in recent years the dam has suffered diverse environmental aggressions including the release of toxic metals. This study presents a recent evaluation of metal contents along the Dam. Samples were collected every three months during the period of winter 2009 to summer 2010. Samples were collected in thirteen points along of the dam, as follows: Rio dos Porcos (Point 1), Summit Control (Point 2), Ilha do Bigua (Point 3), Casa Caida (Point 4), Barragem (Point 5), Foz de Taquacetuba (Point 6), Braco Borore (Point 7), Foz de Borore (Point 8), Alvarenga (Point 9), Pedreira (Point 10), Borore's Margin (Point 11), Capivari I's Margin (Point 12) and Capivari II's Margin (Point 13). The determination of Al, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn was performed by using high resolution inductively coupled plasma mass spectrometer (HR-ICPMS). The methodology has been validated using certified reference material Riverine Water Reference Material for Trace Metals provided by National Research Council Canada (NRCC). The sampling points located in the Pedreira, Borore's Margin, Alvarenga, Barragem Taquacetuba, Casa Caida e Ilha do Bigua presented the highest concentrations. The level for Fe, Cu and Ni were higher than the ones reported in the literature and above the limit set by CONAMA 2914/201. (author)

  12. Mine waters of the flooded Příbram uranium deposit

    OpenAIRE

    Lusk, Karel

    2010-01-01

    From the Příbram deposit, which was the largest exploited uranium deposit in the Czech Republic, mine water has been drained under controlled conditions, treated and discharged into the Kocába River since the flooding of the deposit in October 2005. The amount of water drained in this way is determined at any particular moment by the volume of seepage from precipitation and surface water into the underground mine cavities. The draining of overbalance mine waters is carried out at two points t...

  13. Characterization of the Spatial and Temporal Variations of Submarine Groundwater Discharge Using Electrical Resistivity and Seepage Measurements

    Science.gov (United States)

    Durand, Josephine Miryam Kalyanie

    Submarine groundwater discharge (SGD) encompasses all fluids crossing the sediment/ocean interface, regardless of their origin, composition or driving forces. SGD provides a pathway for terrestrial contaminants that can significantly impact coastal ecosystems. Overexploitation of groundwater resources can decrease SGD which favors seawater intrusion at depth. Understanding SGD is therefore crucial for water quality and resource management. Quantifying SGD is challenging due to its diffuse and heterogeneous nature, in addition to significant spatio-temporal variations at multiple scales. In this thesis, an integrated approach combining electrical resistivity (ER) surveys, conductivity and temperature point measurements, seepage rates using manual and ultrasonic seepage meters, and pore fluid salinities was used to characterize SGD spatio-temporal variations and their implications for contaminant transport at several locations on Long Island, NY. The influence of surficial sediments on SGD distribution was investigated in Stony Brook Harbor. A low-permeability mud layer, actively depositing in the harbor, limits SGD at the shoreline, prevents mixing with seawater and channels a significant volume of freshwater offshore. SGD measured at locations without mud is high and indicates significant mixing between porewater and seawater. A 2D steady-state density-difference numerical model of the harbor was developed using SEAWAT and was validated by our field observations. Temporal variations of SGD due to semi-diurnal tidal forcing were studied in West Neck Bay, Shelter Island, using a 12-hr time-lapse ER survey together with continuous salinity and seepage measurements in the intertidal zone. The observed dynamic patterns of groundwater flux and salinity distribution disagree with published standard transient state numerical models, suggesting the need for developing more specific models of non-homogeneous anisotropic aquifers. SGD distribution and composition were

  14. Probability distribution functions of turbulence in seepage-affected alluvial channel

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Anurag; Kumar, Bimlesh, E-mail: anurag.sharma@iitg.ac.in, E-mail: bimk@iitg.ac.in [Department of Civil Engineering, Indian Institute of Technology Guwahati, 781039 (India)

    2017-02-15

    The present experimental study is carried out on the probability distribution functions (PDFs) of turbulent flow characteristics within near-bed-surface and away-from-bed surfaces for both no seepage and seepage flow. Laboratory experiments were conducted in the plane sand bed for no seepage (NS), 10% seepage (10%S) and 15% seepage (15%) cases. The experimental calculation of the PDFs of turbulent parameters such as Reynolds shear stress, velocity fluctuations, and bursting events is compared with theoretical expression obtained by Gram–Charlier (GC)-based exponential distribution. Experimental observations follow the computed PDF distributions for both no seepage and seepage cases. Jensen-Shannon divergence (JSD) method is used to measure the similarity between theoretical and experimental PDFs. The value of JSD for PDFs of velocity fluctuation lies between 0.0005 to 0.003 while the JSD value for PDFs of Reynolds shear stress varies between 0.001 to 0.006. Even with the application of seepage, the PDF distribution of bursting events, sweeps and ejections are well characterized by the exponential distribution of the GC series, except that a slight deflection of inward and outward interactions is observed which may be due to weaker events. The value of JSD for outward and inward interactions ranges from 0.0013 to 0.032, while the JSD value for sweep and ejection events varies between 0.0001 to 0.0025. The theoretical expression for the PDF of turbulent intensity is developed in the present study, which agrees well with the experimental observations and JSD lies between 0.007 and 0.015. The work presented is potentially applicable to the probability distribution of mobile-bed sediments in seepage-affected alluvial channels typically characterized by the various turbulent parameters. The purpose of PDF estimation from experimental data is that it provides a complete numerical description in the areas of turbulent flow either at a single or finite number of points

  15. Model experiments for {sup 14}C water-age determinations

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, I; Stahl, W; Geyh, M; Fauth, F [Bundesanstalt fuer Bodenforschung, Hannover (Germany)

    1967-05-15

    The {sup 14}C age of water samples is calculated by assuming that fossil carbonate is dissolved by biogenic CO{sub 2} according to the equation x{sub 1} {center_dot} CaCO{sub 3} + (x{sub 1}+y{sub 1}) {center_dot} CO{sub 2} + H{sub 2}O = 2x{sub 1} {center_dot} HCO{sub 3} + y{sub 1} {center_dot} CO{sub 2} where x and y are the number of moles of the two carbon components before and after the dissolution process. In a closed system the relation y{sub 1} = K(T) (x{sub 1}){sup 3} must be satisfied additionally. The equilibrium constant K(T), which depends on the temperature, controls the concentrations of free CO{sub 2} and HCO{sub 3}. To investigate the mechanism of the dissolution, laboratory experiments under controlled conditions were carried out. Non-radioactive CaCO{sub 3}, which had a {delta}{sup 13}C-value of +30 per mille, and radioactive CO{sub 2} with {delta}{sup 13}C = -22 per mille were used. The purpose of these investigations was to check the validity of theoretical assumptions regarding the average {sup 14}C-activity and the {delta}{sup 13}C-value of the total carbon which is dissolved as CO{sub 2} and HCO{sub 3}. Furthermore, it was investigated whether, within the duration of the experiment, a possible exchange takes place between the undissolved carbon present in the CaCO{sub 3} and that present in the HCO{sub 3}. The importance of this lies in the fact that the method of {sup 14}C age determination is based on the assumption that such an exchange does not take place. The experiments which have been performed up to now show that in case of the simple CaCO{sub 3} - CO{sub 2} system, which has been considered first, this assumption is not justified even for a constant water temperature. If variations in the water temperature occur during the history of the water sample, precipitation and redissolution processes influence the {sup 14}C- and {delta}{sup 13}C -values differently. This is due to isotopic fractionation processes between the HCO{sub 3} and CO

  16. Treatment of septic tank effluents by a full-scale capillary seepage soil biofiltration system.

    Science.gov (United States)

    Fan, Chihhao; Chang, Fang-Chih; Ko, Chun-Han; Teng, Chia-Ji; Chang, Tzi-Chin; Sheu, Yiong-Shing

    2009-03-01

    The purpose of this study is to evaluate the efficiency of septic tank effluent treatment by an underground capillary seepage soil biofiltration system in a suburban area of Taipei, Taiwan. In contrast to traditional subsurface wastewater infiltration systems, capillary seepage soil biofiltration systems initially draw incoming influent upwards from the distribution pipe by capillary and siphonage actions, then spread influent throughout the soil biofiltration bed. The underground capillary seepage soil biofiltration system consists of a train of underground treatment units, including one wastewater distribution tank, two capillary seepage soil biofiltration units in series, and a discharge tank. Each capillary seepage soil biofiltration unit contains one facultative digestion tank and one set of biofiltration beds. At the flow rate of 50 m3/day, average influent concentrations of biochemical oxygen demand (BOD), suspended solid (SS), ammonia nitrogen (NH3-N), and total phosphates (TP), were 36.15 mg/L, 29.14 mg/L, 16.05 mg/L, and 1.75 mg/L, respectively. After 1.5 years of system operation, the measured influent and effluent results show that the treatment efficiencies of the soil biofiltration system for BOD, SS, NH3-N, TP, and total coliforms are 82.96%, 60.95%, 67.17%, 74.86%, and 99.99%, respectively.

  17. Effects of Atmospheric Dynamics on CO2 Seepage at Mammoth Mountain, California USA

    Directory of Open Access Journals (Sweden)

    Egemen Ogretim

    2013-12-01

    Full Text Available In the past few decades, atmospheric effects on the variation of seepage from soil have been studied in disciplines such as volcanology, environmental protection, safety and health hazard avoidance. Recently, monitoring of potential leakage from the geologic sequestration of carbon has been added to this list. Throughout these diverse fields, barometric pumping and presence of steady winds are the two most commonly investigated atmospheric factors. These two factors have the effect of pumping gas into and out of the unsaturated zone, and sweeping the gas in the porous medium. This study focuses on two new factors related to atmosphere in order to explain the CO2 seepage anomalies observed at the Horseshoe Lake tree kill near Mammoth Mountain, CA, where the temporal variation of seepage due to a storm event could not be explained by the two commonly studied effects. First, the interaction of the lower atmospheric dynamics and the ground topography is considered for its effect on the seepage variation over an area that is linked through high-porosity, high-permeability soils and/or fracture networks. Second, the regional pressure fronts that impose significant pressure oscillation over an area are studied. The comparison of the computer simulation results with the experimental measurements suggests that the seepage anomaly observed at the Horseshoe Lake Tree Kill could be due to the unsteady effects caused by regional pressure fronts.

  18. determination of trihalomethanes in drinking water in southern

    African Journals Online (AJOL)

    cistvr

    reaction of chlorine with the organic matters or humic acids present in water. The. THMs are .... concentration of humic acid in water, amount of free chlorine present, pH and temperature of ... water using high efficiency solvent extraction. Water ...

  19. Determinants of domestic water consumption in a growing urban ...

    African Journals Online (AJOL)

    cinthia

    principal factor hampering proper and adequate water demand estimation especially in the developing nations. (Ayanshola et al., 2010). Metering of water use which could have helped in efficient water use is not in use in. Nigeria, thus bases for proper definition of the actual water use, according to Bilthas (2008) is lacked.

  20. Contrasting extremes in water-related stresses determine species survival

    Science.gov (United States)

    Bartholomeus, R. P.; Witte, J. P. M.; van Bodegom, P. M.; van Dam, J. C.; Aerts, R.

    2012-04-01

    In temperate climates, soil moisture, in concert with nutrient availability and soil acidity, is the most important environmental filter in determining local plant species composition, as it determines the availability of both oxygen and water to plant roots. These resources are indispensable for meeting the physiological demands of plants. Especially the occurrence of both excessive dry and wet moisture conditions at a particular site has strong implications for the survival of species, because plants need traits that allow them to respond to such counteracting conditions. However, adapting to one stress may go at the cost of the other, i.e. there exists a trade-off in the tolerance for wet conditions and the tolerance for dry conditions. Until now, both large-scale (global) and plot-scale effects of soil moisture conditions on plant species composition have mostly been investigated through indirect environmental measures, which do not include the key soil physical and plant physiological processes in the soil-plant-atmosphere system. Moreover, researchers only determined effects of one of the water-related stresses, i.e. either oxygen or drought stress. In order to quantify both oxygen and drought stress with causal measures, we focused on interacting meteorological, soil physical, microbial, and plant physiological processes in the soil-plant-atmosphere system. We simulated these plant stresses with a novel, process-based approach, incorporating in detail the interacting processes in the soil-plant-atmosphere interface. High variability and extremes in resource availability can be highly detrimental to plant species ('you can only die once'). We show that co-occurrence of oxygen and drought stress reduces the percentage of specialists within a vegetation plot. The percentage of non-specialists within a vegetation plot, however, decreases significantly with increasing stress as long as only one of the stresses prevails, but increases significantly with an

  1. Formation of Box Canyon, Idaho, by megaflood: implications for seepage erosion on Earth and Mars.

    Science.gov (United States)

    Lamb, Michael P; Dietrich, William E; Aciego, Sarah M; Depaolo, Donald J; Manga, Michael

    2008-05-23

    Amphitheater-headed canyons have been used as diagnostic indicators of erosion by groundwater seepage, which has important implications for landscape evolution on Earth and astrobiology on Mars. Of perhaps any canyon studied, Box Canyon, Idaho, most strongly meets the proposed morphologic criteria for groundwater sapping because it is incised into a basaltic plain with no drainage network upstream, and approximately 10 cubic meters per second of seepage emanates from its vertical headwall. However, sediment transport constraints, 4He and 14C dates, plunge pools, and scoured rock indicate that a megaflood (greater than 220 cubic meters per second) carved the canyon about 45,000 years ago. These results add to a growing recognition of Quaternary catastrophic flooding in the American northwest, and may imply that similar features on Mars also formed by floods rather than seepage erosion.

  2. Numerical Modelling of Tailings Dam Thermal-Seepage Regime Considering Phase Transitions

    Directory of Open Access Journals (Sweden)

    Aniskin Nikolay Alekseevich

    2017-01-01

    Full Text Available Statement of the Problem. The article describes the problem of combined thermal-seepage regime for earth dams and those operated in the permafrost conditions. This problem can be solved using the finite elements method based on the local variational formulation. Results. A thermal-seepage regime numerical model has been developed for the “dam-foundation” system in terms of the tailings dam. The effect of heat-and-mass transfer and liquid phase transition in soil interstices on the dam state is estimated. The study with subsequent consideration of these factors has been undertaken. Conclusions. The results of studying the temperature-filtration conditions of the structure based on the factors of heat-and-mass transfer and liquid phase transition have shown that the calculation results comply with the field data. Ignoring these factors or one of them distorts the real situation of the dam thermal-seepage conditions.

  3. A numerical procedure for transient free surface seepage through fracture networks

    Science.gov (United States)

    Jiang, Qinghui; Ye, Zuyang; Zhou, Chuangbing

    2014-11-01

    A parabolic variational inequality (PVI) formulation is presented for the transient free surface seepage problem defined for a whole fracture network. Because the seepage faces are specified as Signorini-type conditions, the PVI formulation can effectively eliminate the singularity of spillpoints that evolve with time. By introducing a continuous penalty function to replace the original Heaviside function, a finite element procedure based on the PVI formulation is developed to predict the transient free surface response in the fracture network. The effects of the penalty parameter on the solution precision are analyzed. A relative error formula for evaluating the flow losses at steady state caused by the penalty parameter is obtained. To validate the proposed method, three typical examples are solved. The solutions for the first example are compared with the experimental results. The results from the last two examples further demonstrate that the orientation, extent and density of fractures significantly affect the free surface seepage behavior in the fracture network.

  4. Ground Water Quality Determination of former Lake Haramaya ...

    African Journals Online (AJOL)

    Michael Horsfall

    Dawa Water Bureau laboratory and Haramaya University laboratory. ... total colifoms above the guideline value and it reveal the necessity of treatment before use. ... Harer Town Water Supply and Sewerage Authority. ..... The small TDS value.

  5. determinants of residential per capita water demand of makurdi

    African Journals Online (AJOL)

    user

    regression analysis for developing a consumption model. Seven variables were ... other non-governmental organizations have indicated that water supply in not ... 90% of rural areas and 60% of urban areas face water related problems [6].

  6. Determination of selected heavy metals in inland fresh water of ...

    African Journals Online (AJOL)

    Agadaga

    Key words: Heavy metals, freshwater, concentrations, quality, variation, distribution. ... prevalence of heavy metals in inland water of lower River. Niger drain are scarce ..... Niger waters at Ajaokuta were found to be low and within guideline.

  7. Spectrophotometric determination of fluoride in drinking water using ...

    African Journals Online (AJOL)

    2011-03-14

    Mar 14, 2011 ... Fluoride (F-) occurs in almost all waters from trace to high con- centration ... in drinking water can give rise to a number of adverse effects. (WHO ..... amended activated alumina granules. Chem. ... coal in Southwestern China.

  8. Fluorescent determination of graphene quantum dots in water samples

    Energy Technology Data Exchange (ETDEWEB)

    Benítez-Martínez, Sandra; Valcárcel, Miguel, E-mail: qa1meobj@uco.es

    2015-10-08

    This work presents a simple, fast and sensitive method for the preconcentration and quantification of graphene quantum dots (GQDs) in aqueous samples. GQDs are considered an object of analysis (analyte) not an analytical tool which is the most frequent situation in Analytical Nanoscience and Nanotechnology. This approach is based on the preconcentration of graphene quantum dots on an anion exchange sorbent by solid phase extraction and their subsequent elution prior fluorimetric analysis of the solution containing graphene quantum dots. Parameters of the extraction procedure such as sample volume, type of solvent, sample pH, sample flow rate and elution conditions were investigated in order to achieve extraction efficiency. The limits of detection and quantification were 7.5 μg L{sup −1} and 25 μg L{sup −1}, respectively. The precision for 200 μg L{sup −1}, expressed as %RSD, was 2.8%. Recoveries percentages between 86.9 and 103.9% were obtained for two different concentration levels. Interferences from other nanoparticles were studied and no significant changes were observed at the concentration levels tested. Consequently, the optimized procedure has great potential to be applied to the determination of graphene quantum dots at trace levels in drinking and environmental waters. - Highlights: • Development of a novel and simple method for determination of graphene quantum dots. • Preconcentration of graphene quantum dots by solid phase extraction. • Fluorescence spectroscopy allows fast measurements. • High sensitivity and great reproducibility are achieved.

  9. Determination of oestrogen hormones in raw and treated water ...

    African Journals Online (AJOL)

    Hormones in water samples have been classified as 'emerging pollutants' and may pose a potential risk for humans. Hormones can be found in both surface and ground water at low concentrations. These compounds enter water streams through wastewater treatment plants (WWTP) and may elicit endocrine disruption to ...

  10. Gas-Chromatographic Determination Of Water In Freon PCA

    Science.gov (United States)

    Melton, Donald M.

    1994-01-01

    Gas-chromatographic apparatus measures small concentrations of water in specimens of Freon PCA. Testing by use of apparatus faster and provides greater protection against accidental contamination of specimens by water in testing environment. Automated for unattended operation. Also used to measure water contents of materials, other than Freon PCA. Innovation extended to development of purgeable sampling accessory for gas chromatographs.

  11. Determination of trihalomethanes in water samples: A review

    Energy Technology Data Exchange (ETDEWEB)

    Perez Pavon, Jose Luis [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias Quimicas, Universidad de Salamanca, 37008 Salamanca (Spain)], E-mail: jlpp@usal.es; Herrero Martin, Sara; Garcia Pinto, Carmelo; Moreno Cordero, Bernardo [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias Quimicas, Universidad de Salamanca, 37008 Salamanca (Spain)

    2008-11-23

    This article reviews the most recent literature addressing the analytical methods applied for trihalomethanes (THMs) determination in water samples. This analysis is usually performed with gas chromatography (GC) combined with a preconcentration step. The detectors most widely used in this type of analyses are mass spectrometers (MS) and electron capture detectors (ECD). Here, we review the analytical characteristics, the time required for analysis, and the simplicity of the optimised methods. The main difference between these methods lies in the sample pretreatment step; therefore, special emphasis is placed on this aspect. The techniques covered are direct aqueous injection (DAI), liquid-liquid extraction (LLE), headspace (HS), and membrane-based techniques. We also review the main chromatographic columns employed and consider novel aspects of chromatographic analysis, such as the use of fast gas chromatography (FGC). Concerning the detection step, besides the common techniques, the use of uncommon detectors such as fluorescence detector, pulsed discharge photoionization detector (PDPID), dry electrolytic conductivity detector (DELCD), atomic emission detector (AED) and inductively coupled plasma-mass spectrometry (ICP-MS) for this type of analysis is described.

  12. Comparison of Scour and Flow Characteristics Around Circular and Oblong Bridge Piers in Seepage Affected Alluvial Channels

    Science.gov (United States)

    Chavan, Rutuja; Venkataramana, B.; Acharya, Pratik; Kumar, Bimlesh

    2018-06-01

    The present study examines scour geometry and turbulent flow characteristics around circular and oblong piers in alluvial channel with downward seepage. Experiments were conducted in plane sand bed of non-uniform sand under no seepage, 10% seepage and 15% seepage conditions. Scour depth at oblong pier is significantly lesser than the scour depth at circular one. However, the scour depth at both piers reduces with downward seepage. The measurements show that the velocity and Reynolds stresses are negative near the bed at upstream of piers where the strong reversal occurs. At downstream of oblong pier near the free surface, velocity and Reynolds stresses are less positive; whereas, they are negative at downstream of circular pier. The streamline shape of oblong pier leads to reduce the strength of wake vortices and consequently reversal flow at downstream of pier. With application of downward seepage turbulent kinetic energy is decreasing. The results show that the wake vortices at oblong pier are weaker than the wake vortices at circular pier. The strength of wake vortices diminishes with downward seepage. The Strouhal number is lesser for oblong pier and decreases with downward seepage for both oblong and circular piers.

  13. H-Area Seepage Basins groundwater monitoring report -- third and fourth quarters 1993. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Butler, C.T.

    1994-03-01

    During the second half of 1993, the groundwater at the H-Area Seepage Basins (HASB) was monitored in compliance with the September 30, 1992, modification of South Carolina Hazardous Waste Permit SC1-890-008-989. A detailed description of the uppermost aquifer is included in the Resource Conservation and Recovery Act Part B post-closure care permit application for the H-Area Hazardous Waste Management Facility submitted to the South Carolina Department of Health and Environmental Control (SCDHEC) in December 1990. Beginning first quarter 1993, the HASB`s Groundwater Protection Standard (GWPS), established in Appendix 3D-A of the cited permit, became the standard for comparison. Historically as well as currently, nitrate, nonvolatile beta, and tritium have been among the primary constituents to exceed standards. Other radionuclides and hazardous constitutents also exceeded the GWPS in the groundwater at the HASB (notably aluminum, iodine-129, strontium-90, technetium-99, and zinc) during the second half of 1993. Elevated constituents were found primarily in Aquifer Zone 2B{sub 2} and in the upper portion of Aquifer Zone 2B{sub 1}. However, constituents exceeding standards also occurred in several wells screened in the lower portion of Aquifer Zone 2B{sub 1} and Aquifer Unit 2A. Isoconcentration/isoactivity maps include in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units during the second half of 1993. Water-level maps indicate that the groundwater flow rates and directions at the HASB have remained relatively constant since the basins ceased to be active in 1988.

  14. H-Area Seepage Basins groundwater monitoring report -- third and fourth quarters 1993

    International Nuclear Information System (INIS)

    Butler, C.T.

    1994-03-01

    During the second half of 1993, the groundwater at the H-Area Seepage Basins (HASB) was monitored in compliance with the September 30, 1992, modification of South Carolina Hazardous Waste Permit SC1-890-008-989. A detailed description of the uppermost aquifer is included in the Resource Conservation and Recovery Act Part B post-closure care permit application for the H-Area Hazardous Waste Management Facility submitted to the South Carolina Department of Health and Environmental Control (SCDHEC) in December 1990. Beginning first quarter 1993, the HASB's Groundwater Protection Standard (GWPS), established in Appendix 3D-A of the cited permit, became the standard for comparison. Historically as well as currently, nitrate, nonvolatile beta, and tritium have been among the primary constituents to exceed standards. Other radionuclides and hazardous constitutents also exceeded the GWPS in the groundwater at the HASB (notably aluminum, iodine-129, strontium-90, technetium-99, and zinc) during the second half of 1993. Elevated constituents were found primarily in Aquifer Zone 2B 2 and in the upper portion of Aquifer Zone 2B 1 . However, constituents exceeding standards also occurred in several wells screened in the lower portion of Aquifer Zone 2B 1 and Aquifer Unit 2A. Isoconcentration/isoactivity maps include in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units during the second half of 1993. Water-level maps indicate that the groundwater flow rates and directions at the HASB have remained relatively constant since the basins ceased to be active in 1988

  15. Final technology report for D-Area oil seepage basin bioventing optimization test, environmental restoration support

    International Nuclear Information System (INIS)

    Radway, J.C.; Lombard, K.H.; Hazen, T.C.

    1997-01-01

    One method proposed for the cleanup of the D-Area Oil Seepage Basin was in situ bioremediation (bioventing), involving the introduction of air and gaseous nutrients to stimulate contaminant degradation by naturally occurring microorganisms. To test the feasibility of this approach, a bioventing system was installed at the site for use in optimization testing by the Environmental Biotechnology Section of the Savannah River Technology Center. During the interim action, two horizontal wells for a bioventing remediation system were installed eight feet below average basin grade. Nine piezometers were also installed. In September of 1996, a generator, regenerative blower, gas cylinder station, and associated piping and nutrient injection equipment were installed at the site and testing was begun. After baseline characterization of microbial activity and contaminant degradation at the site was completed, four injection campaigns were carried out. These consisted of (1) air alone, (2) air plus triethylphosphate (TEP), (3) air plus nitrous oxide, and (4) air plus methane. This report describes results of these tests, together with conclusions and recommendations for further remediation of the site. Natural biodegradation rates are high. Oxygen, carbon dioxide, and methane levels in soil gas indicate substantial levels of baseline microbial activity. Oxygen is used by indigenous microbes for biodegradation of organics via respiration and hence is depleted in the soil gas and water from areas with high contamination. Carbon dioxide is elevated in contaminated areas. High concentrations of methane, which is produced by microbes via fermentation once the oxygen has been depleted, are found at the most contaminated areas of this site. Groundwater measurements also indicated that substantial levels of natural contaminant biodegradation occurred prior to air injection

  16. water quality determination of rainwater harvesting birkas in harshin

    African Journals Online (AJOL)

    Osondu

    2012-03-14

    Mar 14, 2012 ... samples, 78.7 % exceed the standard COD value for surface water. Birkas with coliform ... Keywords: Harvesting, Birka, Physical, Chemical, Microbiology. Around 1.1 .... disinfection of water with lower pH value of less than 8 ...

  17. [Determination of the redox potential of water saturated with hydrogen].

    Science.gov (United States)

    Piskarev, I M; Ushkanov, V A; Aristova, N A; Likhachev, P P; Myslivets, T C

    2010-01-01

    It has been shown that the redox potential of water saturated with hydrogen is -500--700 mV. The time of the establishment of the potential is 24 h. The potential somewhat increases with increasing volume of hydrogen introduced to a reservoir with water and practically does not depend on the presence of additions in water, provided these additions are not reduced by hydrogen. The pH value of water does not change after the addition of water. In a glass vessel with a metallic cover resting on the side, no decrease in potential during the 2.5-month storage was observed. In plastic bottles, the content of hydrogen decreased; on storage for more than two weeks, it disappeared almost completely, and as a result, the potential increased after storage for three to four weeks to a level near zero. In an open vessel, the potential remained negative for two days.

  18. Determining the water content in concrete by gamma scattering method

    International Nuclear Information System (INIS)

    Priyada, P.; Ramar, R.; Shivaramu

    2014-01-01

    Highlights: • Gamma scattering technique for estimation of water content in concrete is given. • The scattered intensity increases with the volumetric water content. • Attenuation correction is provided to the scattered intensities. • Volumetric water content of 137 Cs radioactive source and a high resolution HPGe detector based energy dispersive gamma ray spectrometer. Concrete samples of uniform density ≈2.4 g/cm 3 are chosen for the study and the scattered intensities found to vary with the amount of water present in the specimen. The scattered intensities are corrected for attenuation effects and the results obtained with reference to a dry sample are compared with those obtained by gravimetrical and gamma transmission methods. A good agreement is seen between gamma scattering results and those obtained by gravimetric and transmission methods within accuracy of 6% and <2% change in water content can be detected

  19. The Seepage Simulation of Single Hole and Composite Gas Drainage Based on LB Method

    Science.gov (United States)

    Chen, Yanhao; Zhong, Qiu; Gong, Zhenzhao

    2018-01-01

    Gas drainage is the most effective method to prevent and solve coal mine gas power disasters. It is very important to study the seepage flow law of gas in fissure coal gas. The LB method is a simplified computational model based on micro-scale, especially for the study of seepage problem. Based on fracture seepage mathematical model on the basis of single coal gas drainage, using the LB method during coal gas drainage of gas flow numerical simulation, this paper maps the single-hole drainage gas, symmetric slot and asymmetric slot, the different width of the slot combined drainage area gas flow under working condition of gas cloud of gas pressure, flow path diagram and flow velocity vector diagram, and analyses the influence on gas seepage field under various working conditions, and also discusses effective drainage method of the center hole slot on both sides, and preliminary exploration that is related to the combination of gas drainage has been carried on as well.

  20. Seepage Analysis of Upper Gotvand Dam Concerning Gypsum Karstification (2D and 3D Approaches)

    DEFF Research Database (Denmark)

    Sadrekarimi, Jamshid; Kiyani, Majid; Fakhri, Behnam

    2011-01-01

    Upper Gotvand Dam is constructed on the Karun River at the south west of Iran. In this paper, 2D and 3D models of the dam together with the foundation and abutments were established, and several seepage analyses were carried out. Then, the gypsum veins that are scattered throughout the foundation...

  1. Statement of Basis/Proposed Plan for the Motor Shops Seepage Basin (716-A); FINAL

    International Nuclear Information System (INIS)

    Palmer, E.

    1998-01-01

    The purpose of this plan is to describe the preferred alternative for addressing the Motor Shops Seepage Basin located at the Savannah River site in Aiken County, Aiken, South Carolina and to provide an opportunity for public input into the remedial action selection process

  2. Soil water availability and rooting depth as determinants of hydraulic architecture of Patagonian woody species

    Science.gov (United States)

    Sandra J. Bucci; Fabian G. Scholz; Guillermo Goldstein; Frederick C. Meinzer; Maria E. Arce

    2009-01-01

    We studied the water economy of nine woody species differing in rooting depth in a Patagonian shrub steppe from southern Argentina to understand how soil water availability and rooting depth determine their hydraulic architecture. Soil water content and potentials, leaf water potentials (Leaf) hydraulic conductivity, wood density (Pw), rooting depth, and specific leaf...

  3. Experimental infrared measurements for hydrocarbon pollutant determination in subterranean waters

    NARCIS (Netherlands)

    Lay-Ekuakille, A.; Palamara, I.; Caratelli, D.; Morabito, F.C.

    2013-01-01

    Subterranean waters are often polluted by industrial and anthropic effluents that are drained in subsoil. To prevent and control pollution, legislations of different developed countries require an online monitoring measurement, especially for detecting organic solvents (chlorinated and unchlorinated

  4. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    NICO

    radiation balance.4,5 Major water-soluble inorganic ions are associated with atmospheric ... molecular weight carboxylic acids in aerosol samples collected from a rural ... include biomass burning, agriculture, livestock and soil dust. Tropical ...

  5. trace element determination in municipal water supply of Damaturu

    African Journals Online (AJOL)

    DR. AMINU

    been attributed to human interference, proliferation of industries, and recent ... to chickens for disease management. Similarly, pig ... depends mainly on underground water resources which are .... G.G. (2004). General Chemistry 7th Edition.

  6. Ground-water pollution determined by boron isotope systematics

    International Nuclear Information System (INIS)

    Vengosh, A.; Kolodny, Y.; Spivack, A.J.

    1998-01-01

    Boron isotopic systematics as related to ground-water pollution is reviewed. We report isotopic results of contaminated ground water from the coastal aquifers of the Mediterranean in Israel, Cornia River in north-western Italy, and Salinas Valley, California. In addition, the B isotopic composition of synthetic B compounds used for detergents and fertilizers was investigated. Isotopic analyses were carried out by negative thermal ionization mass spectrometry. The investigated ground water revealed different contamination sources; underlying saline water of a marine origin in saline plumes in the Mediterranean coastal aquifer of Israel (δ 11 B=31.7 per mille to 49.9 per mille, B/Cl ratio ∼1.5x10 -3 ), mixing of fresh and sea water (25 per mille to 38 per mille, B/Cl∼7x10 -3 ) in saline water associated with salt-water intrusion to Salinas Valley, California, and a hydrothermal contribution (high B/Cl of ∼0.03, δ 11 B=2.4 per mille to 9.3 per mille) in ground water from Cornia River, Italy. The δ 11 B values of synthetic Na-borate products (-0.4 per mille to 7.5 per mille) overlap with those of natural Na-borate minerals (-0.9 per mille to 10.2 per mille). In contrast, the δ 11 B values of synthetic Ca-borate and Na/Ca borate products are significantly lower (-15 per mille to -12.1 per mille) and overlap with those of the natural Ca-borate minerals. We suggest that the original isotopic signature of the natural borate minerals is not modified during the manufacturing process of the synthetic products, and it is controlled by the crystal chemistry of borate minerals. The B concentrations in pristine ground-waters are generally low ( 11 B=39 per mille), salt-water intrusion and marine-derived brines (40 per mille to 60 per mille) are sharply different from hydrothermal fluids (δ 11 B=10 per mille to 10 per mille) and anthropogenic sources (sewage effluent: δ 11 B=0 per mille to 10 per mille; boron-fertilizer: δ 11 B=-15 per mille to 7 per mille). some

  7. Determining the water cut and water salinity in an oil-water flowstream by measuring the sulfur content of the produced oil

    International Nuclear Information System (INIS)

    Smith, H.D.; Arnold, D.M.

    1980-01-01

    A technique for detecting water cut and water salinity in an oil/water flowstream in petroleum refining and producing operations is described. The fluid is bombarded with fast neutrons which are slowed down and then captured producing gamma spectra characteristic of the fluid material. Analysis of the spectra indicates the relative presence of the elements sulfur, hydrogen and chlorine and from the sulfur measurement, the oil cut (fractional oil content) of the fluid is determined, enabling the water cut to be found. From the water cut, water salinity can also be determined. (U.K.)

  8. Concentrations of arsenic in brackish lake water : Application of tristimulus colorimetric determination

    OpenAIRE

    Rahman, Md. Mustafizur; Seike, Yasushi; Okumura, Minoru

    2006-01-01

    The evaluation of a simple and rapid tristimulus colorimetric method for the determination of arsenic in brackish waters and its application to brackish water samples taken from brackish Lake Nakaumi are described. The determinations of arsenic in brackish water samples were made satisfactorily independent of sample salinity. By applying this method to lake water samples, the distributions and behaviors of arsenic in the lake and their controlling factors were clarified, such as seasonal vari...

  9. Effect of pore structure on the seepage characteristics of tight sandstone reservoirs: A case study of Upper Jurassic Penglaizhen Fm reservoirs in the western Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Liqiang Sima

    2017-01-01

    Full Text Available Tight sandstone reservoirs are characterized by complex pore structures and strong heterogeneity, and their seepage characteristics are much different from those of conventional sandstone reservoirs. In this paper, the tight sandstone reservoirs of Upper Jurassic Penglaizhen Fm in western Sichuan Basin were analyzed in terms of their pore structures by using the data about physical property, mercury injection and nuclear magnetic resonance (NMR tests. Then, the seepage characteristics and the gas–water two-phase migration mechanisms and distribution of tight sandstone reservoirs with different types of pore structures in the process of hydrocarbon accumulation and development were simulated by combining the relative permeability experiment with the visual microscopic displacement model. It is shown that crotch-like viscous fingering occurs in the process of gas front advancing in reservoirs with different pore structures. The better the pore structure is, the lower the irreducible water saturation is; the higher the gas-phase relative permeability of irreducible water is, the more easily the gas reservoir can be developed. At the late stage of development, the residual gas is sealed in reservoirs in the forms of bypass, cutoff and dead end. In various reservoirs, the interference between gas and water is stronger, so gas and water tends to be produced simultaneously. The sealed gas may reduce the production rate of gas wells significantly, and the existence of water phase may reduce the gas permeability greatly; consequently, the water-bearing low-permeability tight sandstone gas reservoirs reveal serious water production, highly-difficult development and low-recovery percentage at the late stage, which have adverse impacts on the effective production and development of gas wells.

  10. SIMULATION OF RAINFALL AND SEEPAGE FLOW ON UNSATURATED SOIL BY A SEEPAGE-DEFORMATION COUPLED METHOD SIMULACIÓN DE LLUVIA E INFILTRACIÓN EN SUELOS PARCIALMENTE SATURADOS USANDO UN METODO ACOPLADO INFILTRACIÓN-DEFORMACIÓN

    Directory of Open Access Journals (Sweden)

    Edwin García-Aristizábal

    2012-06-01

    Full Text Available This paper presents an application for the analysis of structures formed by unsaturated layered soils subjected to rainfall and seepage flow; the results are part of a current research project on rainfall infiltration. A three-phase coupled infiltration-deformation method for unsaturated soil was used for the numerical analysis. The effects of the water permeability and horizontal drainage on the distribution of seepage flow velocities, saturation, and generation of deformations for an unsaturated layered embankment were investigated. The results show that the generation of deformation on the embankment surface highly depends on the water permeability of the soil. In addition, through horizontal drainage simulations, the advantage of this type of solution for decreasing the pore water pressures on the back of the slope embankment, thus avoiding local failure (erosion, is shown.Este artículo presenta una aplicación para el análisis de estructuras compuestas por suelos parcialmente saturados que están sometidas al efecto de la lluvia y la infiltración; los resultados hacen parte de una investigación en curso relacionada con infiltración de aguas lluvias. Para los análisis numéricos se utilizó un método trifásico acoplado de infiltración-deformación. Se investigaron los efectos que tienen la permeabilidad y el drenaje lateral en la distribución de los vectores de velocidad de infiltración, la saturación y la generación de deformaciones para un terraplén estratificado y parcialmente saturado. Los resultados muestran que la generación de deformación en el talud del terraplén depende, en gran parte, de la permeabilidad del suelo. Adicionalmente, por medio de simulación de drenes horizontales, se muestra la ventaja de este tipo de solución para disminuir las presiones de poros internas en el talud del terraplén, evitando la falla local (erosión.

  11. Determination of Cs-134 and Cs-137 rain water samples

    International Nuclear Information System (INIS)

    Lima, M.F.; Mazzilli, B.

    1988-01-01

    In order to setting an environmental monitoring program at IPEN, was developed a fast and simple methodology for concentration of Cs-134 and Cs-137 in rain water. This procedure consists in the precipitation of cesium and others cathions of its family (NH 4 + , K + and Rb + ) by ammonium molybdophosphate. The measures of the desintegration rates of Cs-134 and Cs-137 was done by gamma spectrometry in a Ge(Li) detector. After setting up the ideal experimental conditions, the procedure was used to analyze four samples of rain water. (author) [pt

  12. Seepage characteristics of the second tertiary combined model

    Directory of Open Access Journals (Sweden)

    Huan ZHAO

    2015-08-01

    Full Text Available The second tertiary combined model experiment zone has been developed in Block B, Field L. The percolation feature of the second tertiary combined develop model shows great importance to rational and efficient development of the reservoir. In order to clearly illuminate its percolation feature, the typical reservoir numerical model is built by Eclipse, which is a reservoir numerical simulation software. The percolation features of original and added perforation interval under the second tertiary combined model are studied, and the variation features of general water-cut, recovery percentage, wellbore pressure, reservoir pressure and water saturation on condition of higher injection rate under the second tertiary combined model are analyzed. The research indicates that the second tertiary combined enhances the recovery of remaining oil on top of thick reservoir by developing and enhancing original perforation interval under water drive, then improves development results by polymer flooding, and gains higher recovery rate by synthetic action of water driver and polymer flooding.

  13. DETERMINING HOW VAPOR PHASE MTBE REACHES GROUND WATER

    Science.gov (United States)

    EPA Region 2 and ORD have funded a RARE project for FY 2005/2006 to evaluate the prospects that MTBE (and other fuel components) in vapors that escape from an underground storage tank (UST) can find its way to ground water produced by monitoring wells at a gasoline filling statio...

  14. Spectrophotometric determination of iron (III) in tap water using 8 ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-14

    Nov 14, 2011 ... Beers law was obeyed in the range of 1 to 14 ug/ml Fe3+. The recovery was between 98.60 ... Federal and state regulations limit the iron content of drinking water to <1 ppm, though iron is easily .... weighed and dissolved in chloroform in a 100 ml volumetric flask and made up to the mark with chloroform.

  15. Source determination of polynuclear aromatic hydrocarbons in water ...

    African Journals Online (AJOL)

    SERVER

    2008-02-05

    Feb 5, 2008 ... transported into an aquatic environment by a number of pathways including fossil fuel distribution, storm water runoff and sewage effluent. Fossil ... formed during the incomplete combustion of coal, oil, gas wood and garbage (Neff, ..... Health impacts of polynuclear aromatic hydrocar- bons. Environmental ...

  16. Experimental partition determination of octanol-water coefficients of ...

    African Journals Online (AJOL)

    An electrochemical method based on square wave voltammetry was developed for the measurement of octanol-water partition coefficient, LogP, for ten ferrocene derivatives. Measured LogP values ranged over two orders of magnitude, between 2.18 for 1- ferrocenylethanol and 4.38 for ferrocenyl-2-nitrophenyl.

  17. Determination of Perchlorate in Bottled Water from Italy

    Directory of Open Access Journals (Sweden)

    Patrizia Iannece

    2013-06-01

    Full Text Available Perchlorate is regarded as an emerging persistent inorganic contaminant. It is widely known that perchlorate is an endocrine disruptor as it competitively inhibits iodide transport in the thyroid gland. As drinking water is the major source of human exposure to perchlorate, its occurrence in commercially available bottled waters purchased in different regions of Italy was investigated. Perchlorate was measured using the rapid, sensitive, and selective LC-ESI-MS/MS (liquid chromatography-electrospray tandem mass spectrometry method by multiple reaction monitoring (MRM of the transition 98.8→82.8, which corresponds to the loss of one oxygen atom in the perchlorate ion (ClO4−→ClO3−. The chlorine isotope ratio (35Cl/37Cl was used as a confirmation tool. The limit of quantification (LOQ for this method was 5 ng/L, and the recovery ranged from 94% to 108%. Perchlorate was detected in 44 of the 62 drinking waters tested, with concentrations ranging from <5 to 75 ng/L. These values are similar in magnitude to those reported in drinking water from the USA and do not pose an immediate health concern.

  18. A rapid method for determining chlorobenzenes in dam water systems

    African Journals Online (AJOL)

    A method using direct immersion solid phase microextraction (DI-SPME) coupled to gas chromatography equipped with a flame ionisation detector (GC-FID) was developed for the analysis of 7 chlorinated benzenes in dam water. The main parameters affecting the DI-SPME process were optimised. The optimised method ...

  19. Determination of nitrate in water by flow-injection analysis

    Czech Academy of Sciences Publication Activity Database

    Mikuška, Pavel; Večeřa, Zbyněk

    2001-01-01

    Roč. 8, č. 1 (2001), s. 115-120 ISSN 1231-7098 R&D Projects: GA ČR GA203/98/0943 Grant - others:COPERNICUS(BE) SUB-AERO EVK2-1999-000327 Institutional research plan: CEZ:AV0Z4031919 Keywords : nitrate * chemiluminescence * water Subject RIV: CB - Analytical Chemistry, Separation

  20. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    Atmospheric aerosol samples of PM2.5 and PM10 were collected in April–May 2011 from a rural site in Tanzania and analyzed for water-soluble inorganic ions and low molecular weight carboxylic acids using ion chromatography. PM2.5 and PM10 low-volume samplers with quartz fibre filters were deployed and aerosol ...

  1. Source determination of polynuclear aromatic hydrocarbons in water ...

    African Journals Online (AJOL)

    SERVER

    2008-02-05

    Feb 5, 2008 ... Department of Chemistry, Delta State University, Abraka, Delta State, Nigeria. Phone: +234 ... tous in nature as evidenced by their detection in sedi- ments, soils, air ... sions of non-combustion derived matter including inad- vertent oil ... composition of the 2, 3 - ring, low molecular weight PAHs in water of ...

  2. The Determination of Anionic Surfactants in Natural and Waste Waters.

    Science.gov (United States)

    Crisp, P. T.; And Others

    1983-01-01

    Background information, procedures, and results of an experiment suitable for measuring subpart per million concentrations of anionic surfactants in natural waters and waste effluents are provided. The experiment required only a spectrophotometer or filter photometer and has been successfully performed by students in an undergraduate environmental…

  3. Determining water reservoir characteristics with global elevation data

    NARCIS (Netherlands)

    van Bemmelen, C. W T; Mann, M.; de Ridder, M.P.; Rutten, M.M.; van de Giesen, N.C.

    2016-01-01

    Quantification of human impact on water, sediment, and nutrient fluxes at the global scale demands characterization of reservoirs with an accuracy that is presently unavailable. This letter presents a new method, based on virtual dam placement, to make accurate estimations of area-volume

  4. Determination of oestrogen hormones in raw and treated water ...

    African Journals Online (AJOL)

    use, via sewage treatment plants. If these compounds are not eliminated by wastewater treatment plants, they can then be discharged to rivers and lakes which are used as sources for drinking water production. Therefore, the presence of such organic contaminants may have a negative impact on the quality of drinking ...

  5. Simulating liquid water for determining its structural and transport properties

    International Nuclear Information System (INIS)

    Arismendi-Arrieta, Daniel; Medina, Juan S.; Fanourgakis, George S.; Prosmiti, Rita; Delgado-Barrio, Gerardo

    2014-01-01

    Molecular dynamics simulations are carried out for calculating structural and transport properties of pure liquid water, such as radial distribution functions and self-diffusion and viscosity coefficients, respectively. We employed reparameterized versions of the ab initio water potential by Niesar, Clementi and Corongiu (NCC). In order to investigate the role of the electrostatic contribution, the partial charges of the NCC model are adjusted so that to reproduce the dipole moment values of the SPC/E, SPC/Fw and TIP4P/2005 water models. The single and collective transport coefficients are obtained by employing the Green–Kubo relations at various temperatures. Additionally, in order to overcome convergence difficulties arising from the long correlation times of the stress-tensor autocorrelation functions, a previously reported fitting scheme was employed. The present results indicate that there is a significant relationship between the dipole moment value of the model, and the calculated transport coefficients. We found that by adjusting the molecular dipole moment of the NCC to the value of the TIP4P/2005, the obtained values for the self-diffusion and viscosity coefficients are in better agreement with experiment, compared to the values obtained with the original NCC model. Even though the predictions of the present model exhibits an overall correct behavior, we conclude that further improvements are still required. In order to achieve that, a careful reparameterization of the repulsion–dispersion terms of the potential model is proposed. Also, the effect of the inclusion of many-body effects such as polarizability, should also be investigated. - Highlights: ► Transport properties of liquid water are important in bio-simulations. ► Self-diffusion coefficient, shear and bulk viscosities calculations from NVE molecular dynamics simulations. ► Their comparison with experimental data provides information on intermolecular forces, and serve to develop water

  6. Determination of arsenic concentration in drinking water from tubewell

    International Nuclear Information System (INIS)

    Molla, N.I.; Basunia, S.; Zaman, Laila; Hossain, S.M.; Miah, R.U.; Rahman, M.

    1998-01-01

    Arsenic contamination in drinking water from tubewells in the north-western and south-western region of Bangladesh has posed a great risk to public health. Most of the affected districts are primarily reported to have arsenic concentration in drinking water more than the permissible level, set by WHO, of 0.01 mg/L. Therefore, use of a reliable analytical technique like instrumental neutron activation analysis (INAA) for bulk sample analysis, covering a wide sampling area, has become an essential task. In this work the analytical results of forty tubewell water samples from two districts, namely Chapainawabganj and Faridpur, are reported. The concentration level of arsenic are found to be 28 to 378 μg/L. The detection limit is 3 μg/L. Tubewell samples, collected from different locations of Chapainawabganj and Faridpur municipal areas, and standard reference material NIST 1643d (water) together with primary standard of arsenic (100 μg/L) were irradiated at the TRIGA Mark-II research reactor, AERE, Savar with a nominal neutron flux about 10 12 cm -2 s -1 for one hour using the Lazy Susan facility. After irradiation, allowing a cooling time of 50-70 hours, radioactivity of the 76 As radionuclide was measured with a high resolution HPGe detector in combination with a PC based S-100 MCA master board packages. The detector was previously calibrated with a set of standard gamma ray sources. The gamma ray spectra were analyzed using gamma-software Peakgr-10 and GANAAS and manually. It has been possible to minimize the contribution of interfering 82 Br and 122 Sb radionuclides and the background of 24Na by optimizing irradiation time, cooling period and counting time. The quality of the analysis has been crossed-checked by analyzing the NIST SRM-1643b with respect to the primary standard of arsenic (100 μg/L). It is concluded that that arsenic concentration level is much higher in underground water of some areas posing serious threat to public health. However, hundred

  7. The optimation of radon-222 determination in water by Lucas cell technique

    International Nuclear Information System (INIS)

    Andrejkovicova, S.; Kuruc, J.; Kovacsova, A.; Mackova, J.; Rajec, P.

    2003-01-01

    The aim of this work was to determine detection efficiency ε, volume activity a v , low detection limit, minimal detection activity for radon. There were collecting several samples of water: water from tap water, mineral water, thermal water, water from wells and bottled drinking water. As we expected, the lowest values of volume activities of radon were reached in bottled drinking water (0.1 - 4.9 Bq/dm 3 ). Higher values were reached in water from tap water and natural mineral water (2.5 - 14.9 Bq/dm 3 ). The highest volume activities of radon were obtained in thermal water and water from wells (17.2 - 107.9 Bq/dm 3 ). Method for determination of radon in water was verified at Institute of Preventive and Clinical Medicine, Bratislava, Slovakia. Results of radon concentration in waters are in accordance with an uppermost - accepted value of radon in water. The volume activity of radon in our samples has never been higher as a limit value has allowed (300 Bq/dm 3 ). (authors)

  8. Rigorous determination of stratospheric water vapor trends from MIPAS observations.

    Science.gov (United States)

    Ceccherini, Simone; Carli, Bruno; Raspollini, Piera; Ridolfi, Marco

    2011-05-09

    The trend of stratospheric water vapor as a function of latitude is estimated by the MIPAS measurements by means of a new method that uses the measurement space solution. The method uses all the information provided by the observations avoiding the artifacts introduced by the a priori information and by the interpolation to different vertical grids. The analysis provides very precise values of the trends that, however, are limited by a relatively large systematic error induced by the radiometric calibration error of the instrument. The results show in the five years from 2005 to 2009 a dependence on latitude of the stratospheric (from 37 to 53 km) water vapor trend with a positive value of (0.41 ± 0.16)%yr-1 in the northern hemisphere and less than 0.16%yr-1 in the southern hemisphere.

  9. Determining The Water Quality of Maruf Dam (Boyabat–Sinop

    Directory of Open Access Journals (Sweden)

    Ekrem MUTLU

    2017-06-01

    Full Text Available In this study, the preliminary findings obtained from 3 sampling points, which represent the whole, on Maruf Irrigation Dam, which is located in Boyabat district of Sinop province, for 12 months between September 2015 and August 2016 were examined. The parameters monitored are temperature, dissolved oxygen, pH, electrical conductivity, total hardness, total alkalinity, chemical oxygen demand, biological oxygen demand, and dissolved anions and cations (sodium, potassium, calcium, magnesium, ammonium, nitrate, phosphate, chloride, sulfate, and sulfite. Because of its low dissolved ionic matter content, Maruf Dam was characterized as an alkali dam with mid-hard water and low electrical conductivity. In terms of parameters A and B of Surface Water Quality Management Regulation, the dam is considered “high-quality” and “unpolluted”. Besides the irrigation purposes, for which the barrage was constructed, the dam can also be used for aquaculture, animal breeding, and farming needs.

  10. Experimental infrared measurements for hydrocarbon pollutant determination in subterranean waters

    OpenAIRE

    Lay-Ekuakille, A.; Palamara, I.; Caratelli, D.; Morabito, F.C.

    2013-01-01

    Subterranean waters are often polluted by industrial and anthropic effluents that are drained in subsoil. To prevent and control pollution, legislations of different developed countries require an online monitoring measurement, especially for detecting organic solvents (chlorinated and unchlorinated ones). Online measurements include both real-time and no real-time measurements. In general, it is difficult to implement real-time measurements in stricto sensu for online acquisitions on aqueous...

  11. Determining the Field Capacity, Wilting point and Available Water ...

    African Journals Online (AJOL)

    Prof. Ogunji

    points in different parts of southeast Nigeria and analyzed for particle size distribution, organic carbon ... Laboratory analysis: Particle size was determined by the pipette method (Gee and Orr, 1994) while organic ..... Soil Report 1985. Federal ...

  12. Method of core thermodynamic reliability determination in pressurized water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, G.; Horche, W. (Ingenieurhochschule Zittau (German Democratic Republic). Sektion Kraftwerksanlagenbau und Energieumwandlung)

    1983-01-01

    A statistical model appropriate to determine the thermodynamic reliability and the power-limiting parameter of PWR cores is described for cases of accidental transients. The model is compared with the hot channel model hitherto applied.

  13. Method of core thermodynamic reliability determination in pressurized water reactors

    International Nuclear Information System (INIS)

    Ackermann, G.; Horche, W.

    1983-01-01

    A statistical model appropriate to determine the thermodynamic reliability and the power-limiting parameter of PWR cores is described for cases of accidental transients. The model is compared with the hot channel model hitherto applied. (author)

  14. A method for the determination of residual beta activity in drinking water samples

    Energy Technology Data Exchange (ETDEWEB)

    Idoeta, R. [Dpto. Ingenieria Nuclear y Mecanica de Fluidos, E. T. S. Ingenieria de Bilbao - Universidad del Pais Vasco (UPV/EHU), Alda. Urquijo s/n. 48013 Bilbao (Spain)], E-mail: raquel.idoeta@ehu.es; Herranz, M.; Abelairas, A.; Legarda, F. [Dpto. Ingenieria Nuclear y Mecanica de Fluidos, E. T. S. Ingenieria de Bilbao - Universidad del Pais Vasco (UPV/EHU), Alda. Urquijo s/n. 48013 Bilbao (Spain)

    2007-09-15

    The determination of residual beta activity in drinking water is usually needed in most monitoring programs. In this work a procedure for its determination is described and expressions for the calculations of detection limits and uncertainties are proposed.

  15. A method for the determination of residual beta activity in drinking water samples

    International Nuclear Information System (INIS)

    Idoeta, R.; Herranz, M.; Abelairas, A.; Legarda, F.

    2007-01-01

    The determination of residual beta activity in drinking water is usually needed in most monitoring programs. In this work a procedure for its determination is described and expressions for the calculations of detection limits and uncertainties are proposed

  16. Rapid determination of radionuclide activity concentrations in contaminated drinking water

    International Nuclear Information System (INIS)

    Medley, P.; Ryan, B.; Bollhofer, A.; Martin, P.; International Atomic Energy Agency, Vienna

    2007-01-01

    As a result of an incident at the Ranger Uranium mine in which drinking water was contaminated with process water, it was necessary to perform quick analysis for naturally occurring uranium and thorium series radionuclide activity concentrations, including 226Ra, 210Pb, 210Po, U and Th isotopes. The methods which were subsequently used are presented here. The techniques used were high-resolution gamma spectrometry, Inductively Coupled Plasma Mass Spectrometry (ICPMS) and high-resolution alpha spectrometry. Routine methods were modified to allow for rapid analyses on priority samples in 1-2 days, with some results for highest priority samples available in less than 1 day. Comparison of initial results obtained through standard procedures, is discussed. An emphasis is placed on high-resolution alpha spectrometry of major alpha-emitting nuclides, specifically 226Ra, 230Th and 238U. The range of uranium concentrations in the samples investigated was from background levels to 6.6ppm. Implications for radiological dose assessment in contamination incidents involving process water are presented. The worst-case scenario for the incident at Ranger Uranium Mine indicates that the maximum committed effective dose to workers was well below the ICRP limit for worker-related dose and below the dose limit for a member of the public, with 230Th being the highest contributor

  17. Development of an optochemical sensor for continuous reversible determination of nitrate in drinking water and ground water

    International Nuclear Information System (INIS)

    Lumpp, R.

    1993-09-01

    An optochemical sensor has been developed for continuous reversible determination of nitrate in drinking water and ground water. The sensor is based on the combination of the anion selective liquid ion exchanger Ni(II[bathophenanthroline] 3 2+ with phenolsulfonephtalein dyes in a polyvinylchloride membrane. (orig.) [de

  18. Determination of potassium concentration in salt water for residual beta radioactivity measurements

    International Nuclear Information System (INIS)

    Suarez-Navarro, J.A.; Pujol, Ll.

    2004-01-01

    High interferences may arise in the determination of potassium concentration in salt water. Several analytical methods were studied to determine which method provided the most accurate measurements of potassium concentration. This study is relevant for radiation protection because the exact amount of potassium in water samples must be known for determinations of residual beta activity concentration. The fitting algorithm of the calibration curve and estimation of uncertainty in potassium determinations were also studied. The reproducibility of the proposed analytical method was tested by internal and external validation. Furthermore, the residual beta activity concentration of several Spanish seawater and brackish river water samples was determined using the proposed method

  19. Stability of infinite slopes under transient partially saturated seepage conditions

    Science.gov (United States)

    Godt, Jonathan W.; ŞEner-Kaya, BaşAk; Lu, Ning; Baum, Rex L.

    2012-05-01

    Prediction of the location and timing of rainfall-induced shallow landslides is desired by organizations responsible for hazard management and warnings. However, hydrologic and mechanical processes in the vadose zone complicate such predictions. Infiltrating rainfall must typically pass through an unsaturated layer before reaching the irregular and usually discontinuous shallow water table. This process is dynamic and a function of precipitation intensity and duration, the initial moisture conditions and hydrologic properties of the hillside materials, and the geometry, stratigraphy, and vegetation of the hillslope. As a result, pore water pressures, volumetric water content, effective stress, and thus the propensity for landsliding vary over seasonal and shorter time scales. We apply a general framework for assessing the stability of infinite slopes under transient variably saturated conditions. The framework includes profiles of pressure head and volumetric water content combined with a general effective stress for slope stability analysis. The general effective stress, or suction stress, provides a means for rigorous quantification of stress changes due to rainfall and infiltration and thus the analysis of slope stability over the range of volumetric water contents and pressure heads relevant to shallow landslide initiation. We present results using an analytical solution for transient infiltration for a range of soil texture and hydrological properties typical of landslide-prone hillslopes and show the effect of these properties on the timing and depth of slope failure. We follow by analyzing field-monitoring data acquired prior to shallow landslide failure of a hillside near Seattle, Washington, and show that the timing of the slide was predictable using measured pressure head and volumetric water content and show how the approach can be used in a forward manner using a numerical model for transient infiltration.

  20. Comparison of total body water determinations in lactating women by anthropometry, water displacement, and deuterium isotope dilution

    International Nuclear Information System (INIS)

    Wong, W.; Butte, N.; Lee, L.; Garza, C.; Klein, P.

    1986-01-01

    To expand the limited data on the total body water in lactating women, the authors have determined total body water contents, in eight subjects from anthropometric measurements, water displacement, and isotope dilution of deuterium oxide. On the day of the study, their skinfold thicknesses were measured over the biceps and triceps muscles and at the suprailiac and subscapular areas. Their body densities were measured by water displacement. Deuterium oxide was administered orally at 100 mg/kg of body weight. One predose milk sample was collected from each subject. The milk samples were defatted by centrifugation and the milk water was reduced to hydrogen gas for hydrogen isotope ratio measurements by gas-isotope-ratio mass spectrometry. The results indicated that total body water in lactating women estimated from anthropometric measurements was 49.7 +/- 3.3% of body weight, by water displacement was 54.9 +/- 7.2%, and by isotope dilution was 50.8 +/- 3.7%

  1. Natural Offshore Oil Seepage and Related Tarball Accumulation on the California Coastline - Santa Barbara Channel and the Southern Santa Maria Basin: Source Identification and Inventory

    Science.gov (United States)

    Lorenson, T.D.; Hostettler, Frances D.; Rosenbauer, Robert J.; Peters, Kenneth E.; Dougherty, Jennifer A.; Kvenvolden, Keith A.; Gutmacher, Christina E.; Wong, Florence L.; Normark, William R.

    2009-01-01

    Oil spillage from natural sources is very common in the waters of southern California. Active oil extraction and shipping is occurring concurrently within the region and it is of great interest to resource managers to be able to distinguish between natural seepage and anthropogenic oil spillage. The major goal of this study was to establish the geologic setting, sources, and ultimate dispersal of natural oil seeps in the offshore southern Santa Maria Basin and Santa Barbara Basins. Our surveys focused on likely areas of hydrocarbon seepage that are known to occur between Point Arguello and Ventura, California. Our approach was to 1) document the locations and geochemically fingerprint natural seep oils or tar; 2) geochemically fingerprint coastal tar residues and potential tar sources in this region, both onshore and offshore; 3) establish chemical correlations between offshore active seeps and coastal residues thus linking seep sources to oil residues; 4) measure the rate of natural seepage of individual seeps and attempt to assess regional natural oil and gas seepage rates; and 5) interpret the petroleum system history for the natural seeps. To document the location of sub-sea oil seeps, we first looked into previous studies within and near our survey area. We measured the concentration of methane gas in the water column in areas of reported seepage and found numerous gas plumes and measured high concentrations of methane in the water column. The result of this work showed that the seeps were widely distributed between Point Conception east to the vicinity of Coal Oil Point, and that they by in large occur within the 3-mile limit of California State waters. Subsequent cruises used sidescan and high resolution seismic to map the seafloor, from just south of Point Arguello, east to near Gaviota, California. The results of the methane survey guided the exploration of the area west of Point Conception east to Gaviota using a combination of seismic instruments. The

  2. F-Area Seepage Basins groundwater monitoring report

    International Nuclear Information System (INIS)

    1992-06-01

    This progress report from the Savannah River Plant for first quarter 1992 includes discussion on the following topics: description of facilities; hydrostratigraphic units; monitoring well nomenclature; integrity of the monitoring well network; groundwater monitoring data; analytical results exceeding standards; tritium, nitrate, and pH time-trend data; water levels; groundwater flow rates and directions; upgradient versus downgradient results

  3. F-Area Seepage Basins groundwater monitoring report

    International Nuclear Information System (INIS)

    1992-09-01

    This progress report from the Savannah River Plant for second quarter 1992 includes discussion on the following topics: description of facilities; hydrostratigraphic units; monitoring well nomenclature; integrity of the monitoring well network; groundwater monitoring data; analytical results exceeding standards; tritium, nitrate, and pH time-trend data; water levels; groundwater flow rates and directions; upgradient versus downgradient results

  4. Technical note: A new method for the determination of water quality ...

    African Journals Online (AJOL)

    The aim of this study was to develop and test a novel screening method for determining water quality. We hypothesised that L-ascorbic acid would be a good indicator of water quality, due to its sensitivity to pollutants. We investigated the absorption spectra of L‑ascorbic acid dissolved at different concentrations in water from ...

  5. 18 CFR 430.7 - Determination of protected areas and restriction on water use.

    Science.gov (United States)

    2010-04-01

    ... protected areas and restriction on water use. 430.7 Section 430.7 Conservation of Power and Water Resources... Determination of protected areas and restriction on water use. In consideration of the foregoing facts and for... a protected area within the meaning and for the purpose of Article 10 of the Delaware River Basin...

  6. Thorium determination in water and biological materials by fission track

    International Nuclear Information System (INIS)

    Melo Ferreira, A.C. de.

    1989-01-01

    As a segment of a research programme on the study of bioaccumulation of radionuclides, in animals and vegetables from Morro do Ferro, Pocos de Caldas, MG, a fission track method for the determination of low levels of thorium in environmental samples was developed as an alternative for alpha spectroscopy. The study was carried out in early alpha spectroscopy samples, containing high levels of 228 Th activity, which makes difficult the 232 Th determination. A dry way method for thorium evaluation was developed. Pieces of membrane filters, containing La F 3 (Th), coupled to Makrofol detectors, were irradiated in the core of a research reactor, IEA-R1 (IPEN). (author)

  7. Assessment of tree toxicity near the F- and H-Area seepage basins of the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C. (ed.) (Westinghouse Savannah River Co., Aiken, SC (USA)); Richardson, C.J. (ed.); Greenwood, K.P.; Hane, M.E.; Lander, A.J. (Duke Univ., Durham, NC (USA))

    1990-12-01

    Areas of tree mortality, originating in 1979, have been documented downslope of the F- and H-Area Seepage Basins. The basins were used as discharge areas for low-level radioactive and nonradioactive waste. Preliminary studies indicated that there are three possible causes of stress: altered hydrology; hazardous chemicals; and nonhazardous chemicals. It was originally hypothesized that the most likely hydrological stressors to Nyssa sylvatica var. biflora were flooding where water levels cover the lenticels for more than 26 percent of the growing season, resulting in low oxygen availability, and toxins produced under anaerobic conditions. In fact, trees began to show stress only flowing a drought year (1977) rather than a wet year. Dry conditions could exacerbate stress by concentrating contaminants, particularly salt. Study of the soil and water chemical parameters in the impacted sites indicated that salt concentrations in the affected areas have produced abnormally high exchangeable sodium percentages. Furthermore, significantly elevated concentrations of heavy metals were found in each impacted site, although no one metal was consistently elevated. Evaluation of the concentrations of various chemicals toxic to Nyssa sylvatica var. biflora revealed that aluminum was probably the most toxic in the F-Area. Manganese, cadmium, and zinc had concentrations great enough to be considered possible causes of tree mortality in the F-Area. Aluminum was the most likely cause of mortality in the H-Area. Controlled experiments testing metal and salt concentration effects on Nyssa sylvatica would be needed to specifically assign cause and effect mortality relationships.

  8. Assessment of tree toxicity near the F- and H-Area seepage basins of the Savannah River Site

    International Nuclear Information System (INIS)

    Loehle, C.; Richardson, C.J.

    1990-12-01

    Areas of tree mortality, originating in 1979, have been documented downslope of the F- and H-Area Seepage Basins. The basins were used as discharge areas for low-level radioactive and nonradioactive waste. Preliminary studies indicated that there are three possible causes of stress: altered hydrology; hazardous chemicals; and nonhazardous chemicals. It was originally hypothesized that the most likely hydrological stressors to Nyssa sylvatica var. biflora were flooding where water levels cover the lenticels for more than 26 percent of the growing season, resulting in low oxygen availability, and toxins produced under anaerobic conditions. In fact, trees began to show stress only flowing a drought year (1977) rather than a wet year. Dry conditions could exacerbate stress by concentrating contaminants, particularly salt. Study of the soil and water chemical parameters in the impacted sites indicated that salt concentrations in the affected areas have produced abnormally high exchangeable sodium percentages. Furthermore, significantly elevated concentrations of heavy metals were found in each impacted site, although no one metal was consistently elevated. Evaluation of the concentrations of various chemicals toxic to Nyssa sylvatica var. biflora revealed that aluminum was probably the most toxic in the F-Area. Manganese, cadmium, and zinc had concentrations great enough to be considered possible causes of tree mortality in the F-Area. Aluminum was the most likely cause of mortality in the H-Area. Controlled experiments testing metal and salt concentration effects on Nyssa sylvatica would be needed to specifically assign cause and effect mortality relationships

  9. Laser-fluorescence determination of trace uranium in hot spring water, geothermal water and tap water in Xi'an Lishan region

    International Nuclear Information System (INIS)

    Ma Wenyan; Zhou Chunlin; Han Feng; Di Yuming

    2002-01-01

    Using the Laser-Fluorescence technique, an investigation was made, adopting the standard mix method, on trace uranium concentrations in hot spring water and geothermal water from Lishan region, and in tap water from some major cities in Shanxi province. Totally 40 samples from 27 sites were investigated. Measurement showed that the tap water contains around 10 -6 g/L of uranium, whose concentrations in both hot spring water and geothermal water are 10 -5 g/L. Most of samples are at normal radioactive background level, some higher contents were determined in a few samples

  10. Decontamination and decommissioning of the SPERT-I seepage pit at the Idaho National Engineering Laboratory. Final report

    International Nuclear Information System (INIS)

    Suckel, R.A.

    1984-11-01

    This report describes the decontamination and decommissioning of the SPERT-I seepage pit. Prior to its decontamination and decommissioning, the seepage pit was surrounded by an earthen dike varying from 2 to 6 ft above the pit bottom. A 6-in., cast iron, underground waste line originated at the pit tank in the reactor building and ran approximately 68 ft to the seepage pit. The soil in the seepage pit contained low-level radioactive contamination. The soil surface was removed to a depth of 2.5 ft and shipped to the Radioactive Waste Management Complex (RWMC). The waste line that contained fixed contamination was removed and also sent to the RWMC. The pit was backfilled with radiologically clean soil, reducing the surface activity to background. A permanent marker was erected over the backfilled pit to indicate that presence of residual subsurface radioactive contamination. 5 references, 26 figures, 3 tables

  11. Operating history and environmental effects of seepage basins in chemical-separations areas of the Savannah River Plant

    International Nuclear Information System (INIS)

    Fenimore, J.W.; Horton, J.H.

    1973-01-01

    This report summarizes the history of operation and monitoring of the earthen seepage basins, presents results of a comprehensive study of radionuclide distribution in groundwater downgradient from the basins, and evaluates past performance and possible future alternatives for these basins

  12. The use of material balanced equation to determine the oil water ...

    African Journals Online (AJOL)

    The oil water contact of an oil reservoir can be determined using some geophysical well logs. However, some of the methods might not be accurate. Therefore the material balanced equation which is an accurate means of formation evaluation is critically analysed in this study and then used to determine the oil water contact ...

  13. Determination of boron in sea water by atomic absorption spectrophotometry

    International Nuclear Information System (INIS)

    Horta, A.M.T.C.; Curtius, A.J.

    1978-01-01

    The chelation-extraction of boric acid with are acid solution of 2-ethyl-1,3 hexanediol in methy1-isobutye-ketone is studied. By this way a simple, quick and precise method for boron determination can be obtained [pt

  14. Proposed test method for determining discharge rates from water closets

    DEFF Research Database (Denmark)

    Nielsen, V.; Fjord Jensen, T.

    At present the rates at which discharge takes place from sanitary appliances are mostly known only in the form of estimated average values. SBI has developed a measuring method enabling determination of the exact rate of discharge from a sanitary appliance as function of time. The methods depends...

  15. Investigation of seepage around the bucket skirt during installation in sand

    DEFF Research Database (Denmark)

    Koteras, Aleksandra Katarzyna; Ibsen, Lars Bo

    or along bucket skirt with known soil condition, bucket geometry and applied suction. The second aim of the study is to evaluate expressions for normalized seepage length, s/h, for different soil combinations and penetration depths. The seepage length is then 7 used to make a prediction of critical...... pressure that will create piping channels at exit, which is near to seabed and to the caisson wall, along bucket wall and at the tip. That is how the limits for suction installation can be assumed. Finally, the critical suction is used for predicting the reduction of penetration resistance and the method...... describing this approach is presented in the report with its assumptions. The method is called AAU CPT-based method and it is a great step in the development of practical design tool for bucket foundation installation process....

  16. A Pore Scale Flow Simulation of Reconstructed Model Based on the Micro Seepage Experiment

    Directory of Open Access Journals (Sweden)

    Jianjun Liu

    2017-01-01

    Full Text Available Researches on microscopic seepage mechanism and fine description of reservoir pore structure play an important role in effective development of low and ultralow permeability reservoir. The typical micro pore structure model was established by two ways of the conventional model reconstruction method and the built-in graphics function method of Comsol® in this paper. A pore scale flow simulation was conducted on the reconstructed model established by two different ways using creeping flow interface and Brinkman equation interface, respectively. The results showed that the simulation of the two models agreed well in the distribution of velocity, pressure, Reynolds number, and so on. And it verified the feasibility of the direct reconstruction method from graphic file to geometric model, which provided a new way for diversifying the numerical study of micro seepage mechanism.

  17. Modelling Technique for the Assessment of the Sub-Soil Drain for Groundwater Seepage Remediation

    Directory of Open Access Journals (Sweden)

    Tajul Baharuddin Mohamad Faizal

    2017-01-01

    Full Text Available Groundwater simulation technique was carried out for examining the performance of sub-soil drain at problematic site area. Subsoil drain was proposed as one of solution for groundwater seepage occurred at the slope face by reducing groundwater table at Taman Botani Park Kuala Lumpur. The simulation technique used Modular Three-Dimensional Finite Difference Groundwater Flow (MODFLOW software. In transient conditions, the results of simulation showed that heads increases surpass 1 to 2 m from the elevation level of the slope area that caused groundwater seepage on slope face. This study attempt to decrease the heads increase surpass by using different sub-soil drain size in simulation technique. The sub-soil drain capable to decline the heads ranges of 1 to 2 m.

  18. Study of Movement and Seepage Along Levees Using DINSAR and the Airborne UAVSAR Instrument

    Science.gov (United States)

    Jones, Cathleen E.; Bawden, Gerald; Deverel, Steven; Dudas, Joel; Hensley, Scott

    2012-01-01

    We have studied the utility of high resolution SAR (synthetic aperture radar) for levee monitoring using UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) data collected along the dikes and levees in California's Sacramento-San Joaquin Delta and along the lower Mississippi River. Our study has focused on detecting and tracking changes that are indicative of potential problem spots, namely deformation of the levees, subsidence along the levee toe, and seepage through the levees, making use of polarimetric and interferometric SAR techniques. Here was present some results of those studies, which show that high resolution, low noise SAR imaging could supplement more traditional ground-based monitoring methods by providing early indicators of seepage and deformation.

  19. Determination of arsenic and bromine in hot spring waters by neutron activation analysis

    International Nuclear Information System (INIS)

    Kikawada, Y.; Kawai, S.; Oi, T.

    2004-01-01

    Concentrations of arsenic and bromine dissolved in hot spring waters have been determined by neutron activation analysis using 0.5 cm 3 of sample waters without any chemical pretreatment. The samples prepared for neutron irradiation were simply pieces of filter papers which were infiltrated with samples. With the results of satisfactorily high accuracy and precision, this analytical method was found to be very convenient for the determinations of arsenic and bromine dissolved in water at ppm to sub-ppm levels. (author)

  20. Comparing methods of determining Legionella spp. in complex water matrices.

    Science.gov (United States)

    Díaz-Flores, Álvaro; Montero, Juan Carlos; Castro, Francisco Javier; Alejandres, Eva María; Bayón, Carmen; Solís, Inmaculada; Fernández-Lafuente, Roberto; Rodríguez, Guillermo

    2015-04-29

    Legionella testing conducted at environmental laboratories plays an essential role in assessing the risk of disease transmission associated with water systems. However, drawbacks of culture-based methodology used for Legionella enumeration can have great impact on the results and interpretation which together can lead to underestimation of the actual risk. Up to 20% of the samples analysed by these laboratories produced inconclusive results, making effective risk management impossible. Overgrowth of competing microbiota was reported as an important factor for culture failure. For quantitative polymerase chain reaction (qPCR), the interpretation of the results from the environmental samples still remains a challenge. Inhibitors may cause up to 10% of inconclusive results. This study compared a quantitative method based on immunomagnetic separation (IMS method) with culture and qPCR, as a new approach to routine monitoring of Legionella. First, pilot studies evaluated the recovery and detectability of Legionella spp using an IMS method, in the presence of microbiota and biocides. The IMS method results were not affected by microbiota while culture counts were significantly reduced (1.4 log) or negative in the same samples. Damage by biocides of viable Legionella was detected by the IMS method. Secondly, a total of 65 water samples were assayed by all three techniques (culture, qPCR and the IMS method). Of these, 27 (41.5%) were recorded as positive by at least one test. Legionella spp was detected by culture in 7 (25.9%) of the 27 samples. Eighteen (66.7%) of the 27 samples were positive by the IMS method, thirteen of them reporting counts below 10(3) colony forming units per liter (CFU l(-1)), six presented interfering microbiota and three presented PCR inhibition. Of the 65 water samples, 24 presented interfering microbiota by culture and 8 presented partial or complete inhibition of the PCR reaction. So the rate of inconclusive results of culture and PCR was 36

  1. Isotope Methods in Determining The Water Budget Elements; Su Buetcesi Elemanlarinin Bulunmasinda Izotop Yoentemi

    Energy Technology Data Exchange (ETDEWEB)

    Oezaydin, V [DSI, Technical Research and Quality Control Department, Ankara (Turkey)

    2002-07-01

    One of the main aims of the water engineers is the determination of the inflows to and outflows from a natural or artificial lake. According to the classical water balance equation inflows (precipitation on the lake surface, surface and subsurface inflows) mines the outflows (evaporation from lake surface, surface and subsurface outflows) should be equal to the volume change in a specified time interval. With the classical water budget equation it is possible to determine the total absolute subsurface inflow mines outflow but it is not possible to determine them separately. The two unknowns could be determined with one more equation. The isotopes, oxygen-18, deuterium or tritium, which are naturally present in water, could provide the extra equation by writing the isotopic mass balance equation. In this study, the theoretical background of isotope technique and application to Mogan Lake, will be presented which is used in determining the water budget of lakes.

  2. Emission of Methane and Heavier Alkanes From the La Brea Tar Pits Seepage Area, Los Angeles

    Science.gov (United States)

    Etiope, G.; Doezema, L. A.; Pacheco, C.

    2017-11-01

    Natural hydrocarbon (oil and gas) seeps are widespread in Los Angeles, California, due to gas migration, along faults, from numerous subsurface petroleum fields. These seeps may represent important natural contributors of methane (CH4) and heavier alkanes (C2-C4) to the atmosphere, in addition to anthropogenic fossil fuel and biogenic sources. We measured the CH4 flux by closed-chamber method from the La Brea Tar Pits park (0.1 km2), one of the largest seepage sites in Los Angeles. The gas seepage occurs throughout the park, not only from visible oil-asphalt seeps but also diffusely from the soil, affecting grass physiology. About 500 kg CH4 d-1 is emitted from the park, especially along a belt of enhanced degassing that corresponds to the 6th Street Fault. Additional emissions are from bubble plumes in the lake within the park (order of 102-103 kg d-1) and at the intersection of Wilshire Boulevard and Curson Avenue (>130 kg d-1), along the same fault. The investigated area has the highest natural gas flux measured thus far for any onshore seepage zone in the USA. Gas migration, oil biodegradation, and secondary methanogenesis altered the molecular composition of the original gas accumulated in the Salt Lake Oil Field (>300 m deep), leading to high C1/C2+ and i-butane/n-butane ratios. These molecular alterations can be important tracers of natural seepage and should be considered in the atmospheric modeling of the relative contribution of fossil fuel (anthropogenic fugitive emission and natural geologic sources) versus biogenic sources of methane, on local and global scales.

  3. Groundwater Seepage Estimation into Amirkabir Tunnel Using Analytical Methods and DEM and SGR Method

    OpenAIRE

    Hadi Farhadian; Homayoon Katibeh

    2015-01-01

    In this paper, groundwater seepage into Amirkabir tunnel has been estimated using analytical and numerical methods for 14 different sections of the tunnel. Site Groundwater Rating (SGR) method also has been performed for qualitative and quantitative classification of the tunnel sections. The obtained results of above mentioned methods were compared together. The study shows reasonable accordance with results of the all methods unless for two sections of tunnel. In these t...

  4. The determination of radiocaesium in sea and fresh waters

    International Nuclear Information System (INIS)

    Baker, C.W.

    1975-10-01

    The caesium is adsorbed on to a cartridge of silica gel impregnated with ammonium molybdophosphate from 50 litres of filtered water, adjusted to pH 2 with nitric acid. The cartridge is then placed in a well crystal detector and gamma counted. An additional separation step is required if zirconium-95/niobium-95 contamination has occurred, as shown by gamma spectrometric analysis of the cartridge. The measurement of caesium-137 and caesium-134 is by conventional γ-spectrometry. The output of the analysing system is ASCII paper tape, and a PDP-8 computer is used to convert this spectral information to activity of caesium-137 and -134 in pCi l -1 at the time of sample collection. (U.K.)

  5. Sr{sup 90} determination in calcareous water; Determination du {sup 90}Sr dans des eaux chargees en calcium

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, P; Pardo, G; Wormser, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The Straub method (ref. 2) for determination of radioactive strontium in water containing calcium is valid within very wide limits, and particularly in the case of residual water from the chemical purification treatment of the radioactive liquid effluent at the C.E.N. Saclay. (author) [French] La methode de Straub (ref. 2) de determination du strontium radioactif dans une eau chargee en calcium est valable dans des limites tres larges et en particulier dans le cas d'eaux residuaires provenant du traitement d'epuration chimique des effluents liquides radioactifs du C.E.N. de Saclay. (auteur)

  6. Quality Assurance Project Plan for the treatability study of in situ vitrification of Seepage Pit 1 in Waste Area Grouping 7 at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    1995-07-01

    This Quality Assurance Project Plan (QAPjP) establishes the quality assurance procedures and requirements to be implemented for the control of quality-related activities for Phase 3 of the Treatability Study (TS) of In Situ Vitrification (ISV) of Seepage Pit 1, ORNL Waste Area Grouping 7. This QAPjP supplements the Quality Assurance Plan for Oak Ridge National Laboratory Environmental Restoration Program by providing information specific to the ISV-TS. Phase 3 of the TS involves the actual ISV melt operations and posttest monitoring of Pit 1 and vicinity. Previously, Phase 1 activities were completed, which involved determining the boundaries of Pit 1, using driven rods and pipes and mapping the distribution of radioactivity using logging tools within the pipes. Phase 2 involved sampling the contents, both liquid and solids, in and around seepage Pit 1 to determine their chemical and radionuclide composition and the spatial distribution of these attributes. A separate QAPjP was developed for each phase of the project. A readiness review of the Phase 3 activities presented QAPjP will be conducted prior to initiating field activities, and an Operational Acceptance, Test (OAT) will also be conducted with no contamination involved. After, the OAT is complete, the ISV process will be restarted, and the melt will be allowed to increase with depth and incorporate the radionuclide contamination at the bottom of Pit 1. Upon completion of melt 1, the equipment will be shut down and mobilized to an adjacent location at which melt 2 will commence

  7. Determination of hydrazine in technological waters of power plants

    International Nuclear Information System (INIS)

    Novak, M.; Hlatky, J.; Santova, E.; Nadasky, A.

    1991-01-01

    The available commercial automatic analyzers for the determination of hydrazine with spectrophotometric detection are described. Analyzers that are manufactured at present in Czechoslovakia can be divided into two groups. The first group involves the commercially available UPFA IV NH industrial analyzer. Experience in the introduction of this analyzer in the conditions of the nuclear power plant secondary circuit bear out the earlier observation of failures in the injection and dispensing of reagents and frequent failures of the mechanical programmer. For the determination of hydrazine, the reagent was dissolved in sulfuric acid, and in a time the analyzer had to be put out of operation due to corrosion problems. A remedy consists in the replacement of sulfuric acid with the less aggressive oxalic acid. Another group of automatic analyzers for the determination of hydrazine is based on the flow injection analysis (FIA) method. Although exhibiting a high throughput, analyzers of this kind put high demands on the purity of reagents. The instruments are better suited to laboratory work, whereas problems can arise in industrial conditions. Based on experience gained in the use of automatic analyzers of the two groups, two new analyzers were designed. The one is based on the flow analysis principle and is of modular design, whereas the other is based on the stopped-flow FIA principle; an adapted flow cell is accommodated in the detector, and the device uses a hydraulic path whose diameter is 2 to 5 mm. The determination of hydrazine occurs in a closed system, the reagent being protected from contact with air; this extends the lifetime of the facility and minimizes personnel exposure to toxic and/or radioactive substances. (author). 5 figs., 2 tabs., 8 refs

  8. Determination of the rare earth elements in marine pore waters and associated sediments

    International Nuclear Information System (INIS)

    Kennedy, H.; Elderfield, H.

    Accurate and precise determinations of natural levels of rare earth elements (R.E.E.) in sea water and pore water are highly reliant upon the size and variability of the analytical blank, the method for determining the yield, and, to a lesser extent, the inherent precision of the instrument used. Isotope dilution mass spectrometry (IDMS) together with ultra-clean room techniques has been successfully used in the determinations of rare earth elements in pore waters. Simultaneous multi-element analysis by inductively coupled plasma atomic emission spectrometry (ICP) provides an alternative to IDMS for a rapid determination of R.E.E. in sediments. (author)

  9. Optimization of Multiple Seepage Piping Parameters to Maximize the Critical Hydraulic Gradient in Bimsoils

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2017-10-01

    Full Text Available Seepage failure in the form of piping can strongly influence the stability of block-in-matrix-soils (bimsoils, as well as weaken and affect the performance of bimsoil structures. The multiple-factor evaluation and optimization play a crucial role in controlling the seepage failure in bimsoil. The aim of this study is to improve the ability to control the piping seepage failure in bimsoil. In this work, the response surface method (RSM was employed to evaluate and optimize the multiple piping parameters to maximize the critical hydraulic gradient (CHG, in combination with experimental modeling based on a self-developed servo-controlled flow-erosion-stress coupled testing system. All of the studied specimens with rock block percentage (RBP of 30%, 50%, and 70% were produced as a cylindrical shape (50 mm diameter and 100 mm height by compaction tests. Four uncertain parameters, such as RBP, soil matrix density, confining pressure, and block morphology were used to fit an optimal response of the CHG. The sensitivity analysis reveals the influential order of the studied factors to CHG. It is found that RBP is the most sensitive factor, the CHG decreases with the increase of RBP, and CHG increases with the increase of confining pressure, soil matrix density, and block angularity.

  10. Faults as Windows to Monitor Gas Seepage: Application to CO2 Sequestration and CO2-EOR

    Directory of Open Access Journals (Sweden)

    Ronald W. Klusman

    2018-03-01

    Full Text Available Monitoring of potential gas seepage for CO2 sequestration and CO2-EOR (Enhanced Oil Recovery in geologic storage will involve geophysical and geochemical measurements of parameters at depth and at, or near the surface. The appropriate methods for MVA (Monitoring, Verification, Accounting are needed for both cost and technical effectiveness. This work provides an overview of some of the geochemical methods that have been demonstrated to be effective for an existing CO2-EOR (Rangely, CA, USA and a proposed project at Teapot Dome, WY, USA. Carbon dioxide and CH4 fluxes and shallow soil gas concentrations were measured, followed by nested completions of 10-m deep holes to obtain concentration gradients. The focus at Teapot Dome was the evaluation of faults as pathways for gas seepage in an under-pressured reservoir system. The measurements were supplemented by stable carbon and oxygen isotopic measurements, carbon-14, and limited use of inert gases. The work clearly demonstrates the superiority of CH4 over measurements of CO2 in early detection and quantification of gas seepage. Stable carbon isotopes, carbon-14, and inert gas measurements add to the verification of the deep source. A preliminary accounting at Rangely confirms the importance of CH4 measurements in the MVA application.

  11. Theoretical and Experimental Investigation of Characteristics of Single Fracture Stress-Seepage Coupling considering Microroughness

    Directory of Open Access Journals (Sweden)

    Shengtong Di

    2017-01-01

    Full Text Available Based on the results of the test among the joint roughness coefficient (JRC of rock fracture, mechanical aperture, and hydraulic aperture proposed by Barton, this paper deduces and proposes a permeability coefficient formula of single fracture stress-seepage coupling considering microroughness by the introduction of effect variables considering the microparticle size and structural morphology of facture surface. Quasi-sandstone fracture of different particle size is made by the laboratory test, and the respective modification is made on the coupled shear-seepage test system of JAW-600 rock. Under this condition, the laboratory test of stress-seepage coupling of fracture of different particle size is carried out. The test results show that, for the different particle-sized fracture surface of the same JRC, the permeability coefficient is different, which means the smaller particle size, the smaller permeability coefficient, and the larger particle size, the larger permeability coefficient; with the increase of cranny hydraulic pressure, the permeability coefficient increases exponentially, and under the same cranny hydraulic pressure, there is relation of power function between the permeability coefficient and normal stress. Meanwhile, according to the theoretical formula, the microroughness coefficient of the fractures with different particle size is obtained by the calculation, and its accuracy and validity are verified by experiments. The theoretical verification values are in good agreement with the measured values.

  12. Determination of Groundwater and Surface Water Qualities at Si Racha, Chon Buri

    International Nuclear Information System (INIS)

    Wangsawang, Jarinee; Naenorn, Warinlada; Khuntong, Soontree; Wongsorntam, Krirk; Udomsomporn, Suchin

    2011-06-01

    Full text: Groundwater (13 wells) and surface water (7 ponds) at Si Racha, Chon Buri province were collected for measurement of water qualities and radionuclides. The water qualities included physical and chemical analysis such as pH, EC, TS, TDS, TSS, TKN, total phosphate, BOD, COD, total hardness and FOG based on standard methods for examination of water and wastewater. Heavy metals (Cd, Cu, Cr, Fe, Mn, Ni and Zn) were analyzed by ICP-AES while total coliform was determined by Multiple Tube Methods. Moreover, radionuclides were analyzed by gamma spectrometer and gross beta and gross alpha were obtained from low background gas proportional counter. Values of most parameters in groundwater were below water qualities standards but all parameters in surface water samples were exceeded water qualities standards. It was found that all radionuclides in water samples were originated from natural uranium and thorium series. The data obtained enabled evaluation of pollutants in groundwater and surface water

  13. Total Body Water Determination: Have We To Adapt Its Determination To The Patient Clinical Status?

    Directory of Open Access Journals (Sweden)

    Almudena Pérez Torres

    2012-06-01

    Conclusion: There is a good concordance between both methods in the determination of the TBW. The Watson formula overestimates the TBW in patients with high %FM and underestimates in those with high FFM. In the clinical practice, it is necessary to adapt the determination of TBW to the patient situation.

  14. Determination of the cavity mode in the water

    Directory of Open Access Journals (Sweden)

    Vikulin Pavel

    2018-01-01

    Full Text Available Ultrasonic oscillations find their wide application in various sectors and industries: metallurgy, chemical and food industries, in engineering, in medicine. This is due to physical and chemical changes when exposed to the sound field. Cavitation in ultrasonic field causes the dispersion and emulsification of certain substances and promotes coagulation and degassing affects of crystallization and dissolution. It is known that ultrasonic vibrations also cause a variety of chemical transformations of substances such as oxidation, recovery, polymerization, and depolymerization. Researchers of cavitation action on the matter find the explanation of these phenomena: shock waves and, consequently, acoustic wind. The experiments were conducted in liquid environment (non-distilled water. The volume of the experimental sample amounted to 10 dm3. Method of the magnetostriction was applied to receive ultrasonic vibration, the principle of which consists in transforming electrical oscillations into mechanical. The level of cavitation was checked in two stages to evaluate the cavitation mode according to the degree of erosion of the artificial barriers and to measure the intensity of cavitation noise in the volume.

  15. Experimental infrared measurements for hydrocarbon pollutant determination in subterranean waters

    Science.gov (United States)

    Lay-Ekuakille, A.; Palamara, I.; Caratelli, D.; Morabito, F. C.

    2013-01-01

    Subterranean waters are often polluted by industrial and anthropic effluents that are drained in subsoil. To prevent and control pollution, legislations of different developed countries require an online monitoring measurement, especially for detecting organic solvents (chlorinated and unchlorinated ones). Online measurements include both real-time and no real-time measurements. In general, it is difficult to implement real-time measurements in stricto sensu for online acquisitions on aqueous effluents since they need to be processed by a modeling. This research presents an experimental measurement system based on infrared (IR) spectroscopy for aqueous effluents containing hydrocarbons and capable of displaying excellent values of pollutant concentrations even in instable conditions; the system is able to detect pollutants either in laminar or turbulent flow. The results show the possibility of avoiding the use of "Pitot tube" that is employed to create a stagnation point in order to convert kinetic energy into potential one. This conversion allows the transformation of a turbulent flow in a laminar flow making easy measurement of pollutants included in an aqueous effluent. Obviously, "Pitot tube" is also used for other fluid effluents. The obtained results have been compared with those produced by means of sophisticated IR instrumentation for laboratory applications.

  16. Determination of pentachlorophenol in water and aquifer sediments by high-performance liquid chromatography

    Science.gov (United States)

    Goerlitz, D.F.

    1981-01-01

    Methods for the determination of pentachlorophenol (PCP) in water and aquifer sediments are presented. Reverse-phase high-performance liquid chromotography employing ion suppression and gradient elution is used. PCP can be determined directly in water at a lower limit of detection Of 0.2 micrograms per liter. For extracts of sediment, PCP can be determined to a lower limit of 1.0 micrograms per kilogram.

  17. Fluorimetric determination of uranium in water; Determinacion fluorimetrica de uranio en aguas

    Energy Technology Data Exchange (ETDEWEB)

    Acosta L, E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: eal@nuclear.inin.mx

    1992-02-15

    The fluorimetric method for the determination of microquantities of uranium in water is described. This method covers the determination of uranium in water in the interval from 0.2 to 50 ppm on 50 ml. of radioactive base sample. These limits can be variable if the volume of the aliquot one of the base sample is changed, as well as the volume of the used aliquot one for to the final determination of uranium. (Author)

  18. Water level determination for transportation projects : mean high water manual, final report, November 2009.

    Science.gov (United States)

    2009-11-01

    To ensure proficient network management and safe usage of navigable waterways especially in waters that are : subject to tides, it is essential that the height of the water at various tidal phases be known. This knowledge is also : essential for prop...

  19. Active hydrocarbon (methane) seepage at the Alboran Sea mud volcanoes indicated by specific lipid biomarkers.

    Science.gov (United States)

    Lopez-Rodriguez, C.; Stadnitskaia, A.; De Lange, G. J.; Martínez-Ruiz, F.; Comas, M.; Sinninghe Damsté, J. S.

    2012-04-01

    Mud volcanoes (MVs) and pockmark fields are known to occur in the Alboran Basin (Westernmost Mediterranean). These MVs occur above a major sedimentary depocenter that includes up to 7 km thick early Miocene to Holocene sequences. MVs located on the top of diapiric structures that originated from undercompacted Miocene clays and olistostromes. Here we provide results from geochemical data-analyses of four gravity cores acquired in the Northern Mud Volcano Field (north of the 36°N): i.e. Perejil, Kalinin and Schneiderś Heart mud expulsion structures. Extruded materials include different types of mud breccias. Specific lipid biomarkers (n-alkanes, hopanes, irregular isoprenoid hydrocarbons and Dialkyl Glycerol Diethers (DGDs) were analysed by gas chromatography (GC) and gas chromatography mass spectrometry (GC-MS). Determination of Glycerol Dialkyl Glycerol Tetraethers (GDGTs) by high performance liquid chromatography-spectrometry (HPLC-MS), and analysis of biomarker δ13C values were performed in selected samples. Lipid biomarker analysis from the three MVs revealed similar n-alkane distributions in all mud breccia intervals, showing significant hydrocarbon-derived signals and the presence of thermally immature organic-matter admixture. This suggests that similar strata fed these MVs. The hemipelagic drapes reveal comparable n-alkane distributions, suggesting that significant upward diffusion of fluids occurs. Distributions of GDGTs are generally accepted as usefull biomarkers to locate the anaerobic oxidation of methane (AOM) in marine sediments. However, our GDGT profiles only reflect the marine thaumarchaeotal signature. There seems to be no archaea producing specific GDGTs involved in AOM in the recovered interval. Evidence of recent activity (i.e., methane gas-bubbling and chemosynthetic fauna at the Perejil MV) and the presence of specific lipid biomarker related with methanotropic archaea (Irregular Isoprenoids and DGDs), however, suggest the existence of

  20. Determination of sources and analysis of micro-pollutants in drinking water

    International Nuclear Information System (INIS)

    Md Pauzi Abdullah; Soh Shiau Chian

    2005-01-01

    The objectives of the study are to develop and validate selected analytical methods for the analysis of micro organics and metals in water; to identify, monitor and assess the levels of micro organics and metals in drinking water supplies; to evaluate the relevancy of the guidelines set in the National Standard of Drinking Water Quality 2001; and to identify the sources of pollution and to carryout risk assessment of exposure to drinking water. The presentation discussed the progress of the work include determination of VOCs (Volatile organic compounds) in drinking water using SPME (Solid phase micro-extraction) extraction techniques, analysis of heavy metals in drinking water, determination of Cr(VI) with ICPES (Inductively coupled plasma emission spectrometry) and the presence of halogenated volatile organic compounds (HVOCs), which is heavily used by agricultural sector, in trace concentrations in waters

  1. Determination of Water Quality Parameters in Sivas - Kurugöl Lake

    Directory of Open Access Journals (Sweden)

    Ekrem Mutlu

    2013-12-01

    Full Text Available Kurugöl Lake; Sivas province Hafik county Kurugöl village located within the boundaries of Sivas province, 54 km, Hafik the town 24 miles away, an area of 8.9 ha altitude of 1362 m, an average depth of 3.4 - 4 m with gypsum plateau on the bottom of the boiling water along with rainfall and snowmelt with the lake is fed naturally. Kurugöl (Hafik - Sivas waters of Lake of the physical and chemical properties during the year changes occurring determining water quality characteristics to reveal the pollution levels are determined, living life in terms of the availability of the detection, water pollution and control regulations by the lake water classification and fishing activities, compliance with were identified. The inland lake in Kurugöl (SKKY according to the classification of water resources in accordance with the parameters measured I-III water quality varies from class.

  2. Key issues for determining the exploitable water resources in a Mediterranean river basin.

    Science.gov (United States)

    Pedro-Monzonís, María; Ferrer, Javier; Solera, Abel; Estrela, Teodoro; Paredes-Arquiola, Javier

    2015-01-15

    One of the major difficulties in water planning is to determine the water availability in a water resource system in order to distribute water sustainably. In this paper, we analyze the key issues for determining the exploitable water resources as an indicator of water availability in a Mediterranean river basin. Historically, these territories are characterized by heavily regulated water resources and the extensive use of unconventional resources (desalination and wastewater reuse); hence, emulating the hydrological cycle is not enough. This analysis considers the Jucar River Basin as a case study. We have analyzed the different possible combinations between the streamflow time series, the length of the simulation period and the reliability criteria. As expected, the results show a wide dispersion, proving the great influence of the reliability criteria used for the quantification and localization of the exploitable water resources in the system. Therefore, it is considered risky to provide a single value to represent the water availability in the Jucar water resource system. In this sense, it is necessary that policymakers and stakeholders make a decision about the methodology used to determine the exploitable water resources in a river basin. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Seepage problem in Papan dam and the treatment

    Energy Technology Data Exchange (ETDEWEB)

    Sharghi, A. [JTMA Co., Tehran (Iran, Islamic Republic of); Palassi, M. [Tehran Univ. (Iran, Islamic Republic of). Dept. of Civil Engineering

    2003-07-01

    The Papan dam in the Krygyz Republic is 97 metres high. It is located in the Osh Oblast, within a narrow and steep sided gorge on the Ak-Bura River, approximately 20 kilometres south of the City of Osh. The impoundment of the dam revealed large inflows of water to the downstream dam through the upper half of the dam and through the joints in the right abutment. A number of options were considered before a treatment method was selected. The causes of the leakage were poor grouting, and joints and fissures in the abutment. The remedial process involved the use of a plastic concrete cutoff wall extended from the crest of the dam to a depth of approximately 70 metres, in addition to the use of a grouting curtain in the right abutment. 2 figs.

  4. Using reactive artificial muscles to determine water exchange during reactions

    International Nuclear Information System (INIS)

    Otero, T F; Martínez, J G; Zaifoglu, B

    2013-01-01

    Artificial muscles based on films of conducting polymers translate film volume variations, driven by electrochemical reactions (Faradaic motors), into macroscopic movements with generation of mechanical energy. The reaction promotes exchange of counterions (anions here) and solvent molecules with the electrolyte. Attributing here both the film volume variation and the movement originated by these exchanges of ions and solvent, the described angles can be used to quantify the exchanged solvent. Different angles described by bending muscles consuming equal driving charges in electrolytes having the same cation and different anions were measured. The number of exchanged counterions is given by the consumed charge and the ion valence: this is a Faradaic reaction. The described angle fraction due to the exchanged anions is given by the number of anions and the crystallographic radius. Taking as reference the anion giving the shorter angle, whatever the consumed charge, the relative number of solvent molecules exchanged by the polymeric membrane during a reversible reaction was determined. Actuators and artificial muscles can be used as useful tools for, at least, an initial study of the solvent exchange during reactions in reactive gels. (paper)

  5. Final Report for the Demonstration of Plasma In-situ Vitrification at the 904-65G K-Reactor Seepage Basin

    Energy Technology Data Exchange (ETDEWEB)

    Blundy, R.F. [Westinghouse Savannah River Company, AIKEN, SC (United States); Zionkowki, P.G.

    1997-12-22

    The In-situ Vitrification (ISV) process potentially offers the most stable waste-form for containment of radiologically contaminated soils while minimizing personnel contamination. This is a problem that is extensive, and at the same time unique, to the US Department of Energy`s (DOE) Weapons Complex. An earlier ISV process utilized joule heating of the soil to generate the subsurface molten glass product. However previous test work has indicated that the Savannah river Site soils (SRS) may not be entirely suitable for vitrification by joule heating due to their highly refractory nature. The concept of utilizing a plasma torch for soil remediation by in-situ vitrification has recently been developed, and laboratory test work on a 100 kW unit has indicated a potentially successful application with SRS soils. The Environmental Restoration Division (ERD) of Westinghouse Savannah River Company (WSRC) conducted the first field scale demonstration of this process at the (904-65G) K-Reactor Seepage Basin in October 1996 with the intention of determining the applicability and economics of the process for remediation of a SRS radioactive seepage basin. The demonstration was successful in completing three vitrification runs, including two consecutive runs that fused together adjacent columns of glass to form a continuous monolith. This report describes the demonstration, documents the engineering data that was obtained, summarizes the process economics and makes recommendations for future development of the process and equipment.

  6. Final Report for the Demonstration of Plasma In-situ Vitrification at the 904-65G K-Reactor Seepage Basin

    International Nuclear Information System (INIS)

    Blundy, R.F.; Zionkowki, P.G.

    1997-01-01

    The In-situ Vitrification (ISV) process potentially offers the most stable waste-form for containment of radiologically contaminated soils while minimizing personnel contamination. This is a problem that is extensive, and at the same time unique, to the US Department of Energy's (DOE) Weapons Complex. An earlier ISV process utilized joule heating of the soil to generate the subsurface molten glass product. However previous test work has indicated that the Savannah river Site soils (SRS) may not be entirely suitable for vitrification by joule heating due to their highly refractory nature. The concept of utilizing a plasma torch for soil remediation by in-situ vitrification has recently been developed, and laboratory test work on a 100 kW unit has indicated a potentially successful application with SRS soils. The Environmental Restoration Division (ERD) of Westinghouse Savannah River Company (WSRC) conducted the first field scale demonstration of this process at the (904-65G) K-Reactor Seepage Basin in October 1996 with the intention of determining the applicability and economics of the process for remediation of a SRS radioactive seepage basin. The demonstration was successful in completing three vitrification runs, including two consecutive runs that fused together adjacent columns of glass to form a continuous monolith. This report describes the demonstration, documents the engineering data that was obtained, summarizes the process economics and makes recommendations for future development of the process and equipment

  7. Subsurface water parameters: optimization approach to their determination from remotely sensed water color data.

    Science.gov (United States)

    Jain, S C; Miller, J R

    1976-04-01

    A method, using an optimization scheme, has been developed for the interpretation of spectral albedo (or spectral reflectance) curves obtained from remotely sensed water color data. This method used a two-flow model of the radiation flow and solves for the albedo. Optimization fitting of predicted to observed reflectance data is performed by a quadratic interpolation method for the variables chlorophyll concentration and scattering coefficient. The technique is applied to airborne water color data obtained from Kawartha Lakes, Sargasso Sea, and Nova Scotia coast. The modeled spectral albedo curves are compared to those obtained experimentally, and the computed optimum water parameters are compared to ground truth values. It is shown that the backscattered spectral signal contains information that can be interpreted to give quantitative estimates of the chlorophyll concentration and turbidity in the waters studied.

  8. Connectivity between surface and deep waters determines prokaryotic diversity in the North Atlantic Deep Water.

    Science.gov (United States)

    Frank, Alexander H; Garcia, Juan A L; Herndl, Gerhard J; Reinthaler, Thomas

    2016-06-01

    To decipher the influence of depth stratification and surface provincialism on the dark ocean prokaryotic community composition, we sampled the major deep-water masses in the eastern North Atlantic covering three biogeographic provinces. Their diversity was evaluated using ordination and canonical analysis of 454 pyrotag sequences. Variance partitioning suggested that 16% of the variation in the bacterial community composition was based on depth stratification while 9% of the variation was due to geographic location. General linear mixed effect models showed that the community of the subsurface waters was connected to the dark ocean prokaryotic communities in different biogeographic provinces. Cluster analysis indicated that some prokaryotic taxa are specific to distinct regions in bathypelagic water masses. Taken together, our data suggest that the dark ocean prokaryotic community composition of the eastern North Atlantic is primed by the formation and the horizontal transport of water masses. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  9. Speciative determination of phosphorus in environmental water by the isotope exchange method

    International Nuclear Information System (INIS)

    Ikeda, N.; Yoshikawa, M.; Murakami, S.; Kunika, J.

    1988-01-01

    An isotope exchage method for the speciative determination of phosphorus (PO 4 3- ,PO 3 3- and total P) in natural water samples is proposed by using the exchange system of molybdophosphate in the aqueous phase and tetraphenylarsonium molybdophosphate in the organic phase. In this exchange system, only PO 4 3- exchanges and is determined. When the sample water is treated with Br 2 water in advance, the amount of PO 4 3- +PO 3 3- can be obtained. When the sample is treated with H 2 SO 4 and HNO 3 , the amount of total P can be determined. (author) 4 refs.; 5 tabs

  10. Anion-exchange enrichment and spectrophotometric determination of uranium in sea-water

    International Nuclear Information System (INIS)

    Kuroda, Rokuro; Oguma, Koichi; Mukai, Noriko; Iwamoto, Masatoshi

    1987-01-01

    A method is proposed for the determination of uranium in sea-water. The uranium is strongly sorbed on a strongly basic anion-exchange resin (Cl - form) from acidified sea-water containing sodium azide (0.3M) and is easily eluted with 1M hydrochloric acid. Uranium in the effluent can be determined spectrophotometrically with Arsenazo III. The combined method allows easy and selective determination of uranium in sea-water without using a sophisticated adsorbent. The overall recovery and precision are satisfactory at the 3 μg/1. level. (author)

  11. Determination of dew absorption by coffee plant through deuterium concentrations in leaf water

    Energy Technology Data Exchange (ETDEWEB)

    Leopoldo, P R [Faculdade de Ciencias Medicas e Biologicas de Botucatu (Brazil); Salati, E; Matsui, E [Centro de Energia Nuclear na Agricultura, Piracicaba (Brazil)

    1975-12-01

    The effect of dew falling on leaves on the water metabolism of the coffee plant (Coffea arabica) is examined. The use of natural stable isotopes variations in plant physiological studies is demonstrated. Water extracted from leaf samples is analysed by mass spectrometry. Analyses of deuterium concentrations in water extracted from plant leaves, dew and nutrient solutions are made. Determination of changes in deuterium concentration in the water of leaves from plants exposed to dew, compared with leaves not exposed to dew, is carried out. Results show that during daytime there is an enrichment in deuterium in water contained in the leaves, while at night the opposite occurs.

  12. Determination of dew absorption by coffee plant through deuterium concentrations in leaf water

    International Nuclear Information System (INIS)

    Leopoldo, P.R.; Salati, E.; Matsui, E.

    1975-01-01

    The effect of dew falling on leaves on the water metabolism of the coffee plant (Coffea arabica) is examined. The use of natural stable isotopes variations in plant physiological studies is demonstrated. Water extracted from leaf samples is analysed by mass spectrometry. Analyses of deuterium concentrations in water extracted from plant leaves, dew and nutrient solutions are made. Determination of changes in deuterium concentration in the water of leaves from plants exposed to dew, compared with leaves not exposed to dew, is carried out. Results show that during daytime there is an enrichment in deuterium in water contained in the leaves, while at night the opposite occurs [pt

  13. Towards a determination of the absorbed dose to water in water for low-energy photon-emitting brachytherapy seeds

    International Nuclear Information System (INIS)

    Schneider, T.; Lange, B.; Selbach, H.J.

    2007-01-01

    An accurate determination of the dose produced by brachytherapy seeds emitting low-energy photons is an important component of the radiotherapeutic process. As yet, the output of these seeds has usually been specified in terms of the air kerma rate. The desired quantity in radiation therapy is, however, the absorbed dose to water inside a water phantom, for which primary standards are not available. For this reason, developments are under way in the Physikalisch - Technische Bundesanstalt to establish a primary standard to determine the absorbed dose to water within a phantom. As a fundamental step towards this aim, a method will be introduced in this publication to determine the water kerma inside a graphite phantom housing an extrapolation chamber. Experimental results will be presented and compared with water kerma values obtained from air kerma measurements in free air and applying a conversion factor to water kerma for the conditions of the experiment. First estimates indicate that the relative uncertainty is of the order of 1% (k 1). (authors)

  14. Determination of strontium in drinking water and consequences of radioactive elements present in drinking water for human health

    OpenAIRE

    Rajković Miloš B.; Stojanović Mirjana D.; Pantelić Gordana K.; Vuletić Vedrana V.

    2006-01-01

    In this paper the analysis of strontium and uranium content in drinking water has been done, indirectly, according to the scale which originates from drinking water in water-supply system of the city of Belgrade. Gamaspectrometric analysis showed the presence of free natural radionuclide in low activities. The activity of 90Sr in scale which is 0.72±0.11 Bq/kg was determined by radiochemical. Because of the small quantities of fur in the house heater this activity can be considered as irrelev...

  15. Determination of the air/water partition coefficient of groundwater radon using liquid scintillation counter

    International Nuclear Information System (INIS)

    Lee, K.Y.; Yoon, Y.Y.; Ko, K.S.

    2010-01-01

    A method was studied for measuring air/water partition coefficient (K air/water ) of groundwater radon by a simple procedure using liquid scintillation counter (LSC). In contrast conventional techniques such as equilibrium partitioning in a closed system or air striping methods, the described method allow for a simple and uncomplicated determination of the coefficient. The (K air/water ) of radon in pure water has been well known quantitatively over a wide range of temperatures. In this work, groundwater samples having high radon concentration instead of distilled water have been used to determine the (K air/water ) of radon in the temperature range of 0-25. Aqueous phase in a closed system was used in this study instead of gaseous phase in conventional methods. Three kinds of groundwater taken from different geologic environments were used to investigate the effect of groundwater properties. With the aim to evaluate the reproducibility of the data an appropriate number of laboratory experiments have been carried out. The results show that tie (K air/water ) of radon in the groundwater is smaller than that in the pure water. However, the temperature effect on the coefficient is similar in the groundwater and the pure water. The method using aqueous phase in a closed system by LSC can be used to determine the (K air/water ) of radon in various groundwaters with a simple procedure. The results will be presented at the NAC-IV conference

  16. SPECTROGRAPHIC DETERMINATION OF BERYLLIUM IN OILFIELD WATERS USING A PLASMA ARC

    Energy Technology Data Exchange (ETDEWEB)

    Collins, A. G.; Pearson, C. A.

    1963-10-15

    Geochemical studies of the distribution of the trace, minor, and major constituents of oilfield waters aid in the exploration for petroleum and other minerals, determination of the origin and distribution of oilfield waters and petroleum, and location of casing leaks and of water pollution sources. The determination of the beryllium and related data should be useful in these studies. An emission spectrographic method utilizing a plasma arc assembly for determining beryllium in oilfield waters, with a sensitivity permitting detection of less than 1 ppb, was developed. Beryllium was extracted from synthetic and natural oilfield waters with chloroform and acetylacetone. The extracts were aspirated directly into the plasma arc, and the beryllium emission intensity was recorded on photographic plates. (auth)

  17. Determination of aluminium and physicochemical parameters in the palm oil estates water supply at Johor, Malaysia.

    Science.gov (United States)

    Siti Farizwana, M R; Mazrura, S; Zurahanim Fasha, A; Ahmad Rohi, G

    2010-01-01

    The study was to determine the concentration of aluminium (Al) and study the physicochemical parameters (pH, total dissolved solids (TDS), turbidity, and residual chlorine) in drinking water supply in selected palm oil estates in Kota Tinggi, Johor. Water samples were collected from the estates with the private and the public water supplies. The sampling points were at the water source (S), the treatment plant outlet (TPO), and at the nearest houses (H1) and the furthest houses (H2) from the TPO. All estates with private water supply failed to meet the NSDWQ for Al with mean concentration of 0.99 ± 1.52 mg/L. However, Al concentrations in all public water supply estates were well within the limit except for one estate. The pH for all samples complied with the NSDWQ except from the private estates for the drinking water supply with an acidic pH (5.50 ± 0.90). The private water supply showed violated turbidity value in the drinking water samples (14.2 ± 24.1 NTU). Insufficient amount of chlorination was observed in the private water supply estates (0.09 ± 0.30 mg/L). Private water supplies with inefficient water treatment served unsatisfactory drinking water quality to the community which may lead to major health problems.

  18. A chromatographic determination of water in non-aqueous phases of solvent extraction systems

    International Nuclear Information System (INIS)

    Lyle, S.J.; Smith, D.B.

    1975-01-01

    The disadvantages of the Karl Fischer method for the determination of water in the non-aqueous phases of solvent extraction systems are pointed out, and a gas chromatographic method is described which is claimed to be potentially capable of overcoming these disadvantages. The method, as described, was developed to satisfy conditions relevant to measurement of the transfer rate of water from an aqueous phase into tri-n-butylphosphate in toluene, but it can be used for water determination in other solvent extraction systems. The apparatus used is described in detail. The concentration of water in water-saturated TBP was found to be 3.56 mol/litre, compared with a value of 3.55 obtained by Karl Fischer titration and previous literature values of 3.59 and 3.57. Measurements of water content in benzene solutions of long chain alkylamines were also sucessfully carried out. (U.K.)

  19. Chromatographic determination of the rate and extent of absorption of air pollutants by sea water

    International Nuclear Information System (INIS)

    Nikolakaki, S.; Vassilakos, C.; Katsanos, N.A.

    1994-01-01

    A simple chromatographic method is developed to determine the rate constant for expulsion of an air pollutant from water or its diffusion parameter in the liquid, the rate constant for chemical reaction of the pollutant with water, its mass transfer coefficient in the liquid, and the partition coefficient between liquid water and air. From these physicochemical parameters, the absorption rate by sea water and, therefore, the depletion rate of a polluting substance from the air can be calculated, together with the equilibrium state of this absorption. The method has been applied to nitrogen dioxide being absorbed by triple-distilled water and by sea water, at various temperatures. From the temperature variation of the reaction rate constant and of the partition coefficient, the activation energy for the reaction and the differential heat of solution were determined. (orig.)

  20. Determination of γ-rays emitting radionuclides in surface water: application of a quantitative biosensing method

    International Nuclear Information System (INIS)

    Wolterbeek, H. Th.; Van der Meer, A. J. G. M.

    1995-01-01

    A quantitative biosensing method has been developed for the determination of γ-rays emitting radionuclides in surface water. The method is based on the concept that at equilibrium the specific radioactivity in the biosensor is equal to the specific radioactivity in water. The method consists of the measurement of both the radionuclide and the related stable isotope (element) in the biosensor and the determination of the element in water. This three-way analysis eliminates problems such as unpredictable biosensor behaviour, effects of water elemental composition or further abiotic parameters on accumulation levels: what remains is the generally high enrichment (bioaccumulation factor BCF) of elements and radionuclides in the biosensor material. Using water plants, the method is shown to be three to five orders of magnitude more sensitive than the direct analysis of water. (author)

  1. Determination of {gamma}-rays emitting radionuclides in surface water: application of a quantitative biosensing method

    Energy Technology Data Exchange (ETDEWEB)

    Wolterbeek, H Th; Van der Meer, A. J. G. M. [Delft University of Technology, Interfaculty Reactor Institute, Mekelweg 15, 2629 JB Delft (Netherlands)

    1995-12-01

    A quantitative biosensing method has been developed for the determination of {gamma}-rays emitting radionuclides in surface water. The method is based on the concept that at equilibrium the specific radioactivity in the biosensor is equal to the specific radioactivity in water. The method consists of the measurement of both the radionuclide and the related stable isotope (element) in the biosensor and the determination of the element in water. This three-way analysis eliminates problems such as unpredictable biosensor behaviour, effects of water elemental composition or further abiotic parameters on accumulation levels: what remains is the generally high enrichment (bioaccumulation factor BCF) of elements and radionuclides in the biosensor material. Using water plants, the method is shown to be three to five orders of magnitude more sensitive than the direct analysis of water. (author)

  2. Determination of water environment standards based on water quality criteria in China: Limitations and feasibilities.

    Science.gov (United States)

    Wang, Tieyu; Zhou, Yunqiao; Bi, Cencen; Lu, Yonglong; He, Guizhen; Giesy, John P

    2017-07-01

    There is a need to formulate water environment standards (WESs) from the current water quality criteria (WQC) in China. To this end, we briefly summarize typical mechanisms applied in several countries with longer histories of developing WESs, and three limitations to formulating WESs in China were identified. After analyzing the feasibility factors including economic development, scientific support capability and environmental policies, we realized that China is still not ready for a complete change from its current nation-wide unified WES system to a local-standard-based system. Thus, we proposed a framework for transformation from WQC to WESs in China. The framework consists of three parts, including responsibilities, processes and policies. The responsibilities include research authorization, development of guidelines, and collection of information, at both national and local levels; the processes include four steps and an impact factor system to establish water quality standards; and the policies include seven specific proposals. Copyright © 2016. Published by Elsevier B.V.

  3. Determining the in situ water content of the Geysers Graywacke of Northern California

    Energy Technology Data Exchange (ETDEWEB)

    Marsh, A.

    1994-12-01

    The water content, porosity and permeability measurements of the Northern California Geysers rocks are used to predict the lifetime of the geothermal resource, which provides 10% of Northern California`s electricity. The Geysers rock was drilled from defunct well SB-15-D, and some cores wee sealed in aluminum tubes to preserve the in situ water content. These cores were sent to the Lawrence Livermore Laboratory to measure the water content. Humidity measurements were taken of the air around a one and a half foot encased core, recovered from a depth of 918.9 feet. Over a seven day period, the humidity reached almost 100% indicating that the air around the core was saturated in water vapor. We believe the sealing method is effective, preserving the in-situ water content. To measure water content, I will use Archimede`s principle to determine the density of the core before and after drying in an oven. Ultrasonic measurements will be taken of the core upon removal from aluminum tube to determine the change of p-wave velocity with change in water content. Water in the pores increases the effective compressibility of the rock therefore increasing the p-velocity. The measured p-wave velocities can then be used in the field to determine in-situ water content. Three dimensional x-ray images will be used to determine the deviations from average density within individual cores. Since the density depends on water content as well as mineralogy, images can show the location of pore fluid and drilling mud. Archimede`s principle, humidity detection, ultrasonics and x-ray scanning are viable methods to measure the in-situ water content and pore water distribution in the graywacke.

  4. Water contentwater of determination of cationic polystyrene sulfonate resins by infrared spectrophotometry

    International Nuclear Information System (INIS)

    Noki, V.

    1987-01-01

    A method of the determination of water content in polystyrene sulfonate ion-exchange resins in the presence of alkaline earth counter-ions by I.R. spectrophotometry is proposed. This method does not hold in the case of transition metal due to the formation of coordinated complexes with water molecules.

  5. Optimization and comparison of three different methods for the determination of Rn-222 in water

    International Nuclear Information System (INIS)

    Belloni, P.; Ingrao, G.; Cavaioli, M.; Notaro, M.; Torri, G.; Vasselli, R.; Mancini, C.; Santaroni, P.

    1995-01-01

    Three different systems for the determination of radon in water have been examined: liquid scintillation counting (LSC), degassification followed by Lucas cell counting (LCC) and gamma counting (GC). Particular care has been devoted to the sampling methodologies of the water. Comparative results for several environmental samples are given. A critical evaluation is also given on the basis of the final aim of the measurements

  6. Uncertainties combined in algae and water in chemical analysis in determinations with ICP-OES

    International Nuclear Information System (INIS)

    Souza, Poliana Santos de

    2014-01-01

    One way to determine if some trace elements in algae and water is through uncertainty calculations. Spectrometry and inductively coupled plasma optical emission (ICP-OES) is widely used in this procedure, because it allows the analysis in waters and areas of solid samples. Thus, some elements (Fe, Ca and Mg) were used to calculate the uncertainty. (author)

  7. Alpha low activity determination from limitter isotopes of uranium, thorium ands radium in natural waters

    International Nuclear Information System (INIS)

    Gascon, J.L.; Crespo, M.T.; Acena, M.L.

    1989-01-01

    A method to concentrate uranium, thorium and radium in natural waters has been developed. The method, based on the adsorbing propert-ies of manganes dioxide, has been applied to determine the alpha emitter isotopes of these elements in drinking water of Madrid. In this work we present the description of the method, the analytical procedu-res and the obtained results. (Author)

  8. Simple Method to Determine the Partition Coefficient of Naphthenic Acid in Oil/Water

    DEFF Research Database (Denmark)

    Bitsch-Larsen, Anders; Andersen, Simon Ivar

    2008-01-01

    The partition coefficient for technical grade naphthenic acid in water/n-decane at 295 K has been determined (K-wo = 2.1 center dot 10(-4)) using a simple experimental technique with large extraction volumes (0.09 m(3) of water). Furthermore, nonequilibrium values at different pH values...

  9. Determination of Biochemical Oxygen Demand of Area Waters: A Bioassay Procedure for Environmental Monitoring

    Science.gov (United States)

    Riehl, Matthew

    2012-01-01

    A graphical method for determining the 5-day biochemical oxygen demand (BOD5) for a body of water is described. In this bioassay, students collect a sample of water from a designated site, transport it to the laboratory, and evaluate the amount of oxygen consumed by naturally occurring bacteria during a 5-day incubation period. An accuracy check,…

  10. Optimization and comparison of three different methods for the determination of Rn-222 in water

    Energy Technology Data Exchange (ETDEWEB)

    Belloni, P.; Ingrao, G. [ENEA CRE, Casaccia AMB-BIO, Roma (Italy); Cavaioli, M.; Notaro, M.; Torri, G.; Vasselli, R. [ANPA, National Environmental Protection Agency, DISP ARA MET, Roma (Italy); Mancini, C. [Nuclear Engineering Department, University `La Sapienza, Roma (Italy); Santaroni, P. [National Institute of Nutrition, Roma (Italy)

    1995-10-19

    Three different systems for the determination of radon in water have been examined: liquid scintillation counting (LSC), degassification followed by Lucas cell counting (LCC) and gamma counting (GC). Particular care has been devoted to the sampling methodologies of the water. Comparative results for several environmental samples are given. A critical evaluation is also given on the basis of the final aim of the measurements.

  11. incidence of heavy metals in kano metropolis drinking water sources

    African Journals Online (AJOL)

    userpc

    corrosion of brass fittings of certain submersible pumps and pipes used in borehole and taps specifically. The contamination of well with heavy metals might be due to seepage of sewage ... Chloride determination (Agumetric method):.

  12. Determination of Chlorine Dioxide and Chlorite in Water Supply Systems by Verified Methods

    Directory of Open Access Journals (Sweden)

    Tkáčová Jana

    2014-07-01

    Full Text Available This work is dedicated to the development and optimization of appropriate analytical methods for the determination of chlorine dioxide and chlorite in drinking water in order to obtain accurate and correct results in the quality control of drinking water. The work deals with the development and optimization of a method for the determination of chlorine dioxide using chlorophenol red. Furthermore, a new spectrophotometric method for the determination of chlorite via bromometry using methyl orange was developed, optimized and validated. An electrochemical method for the determination of chlorite by flow coulometry was also developed, optimized and validated.

  13. Determination of boron in natural waters using atomic-absorption spectrometry with electrothermal atomization

    International Nuclear Information System (INIS)

    Usenko, S.I.; Prorok, M.M.

    1992-01-01

    A method of direct determination of boron in natural waters using atomic-absorption spectrometry with electrothermal atomization was developed. Concomitant elements Si, K, Mg, Na, present in natural waters in the concentration of 0.05-100 mg/cv 3 , do not produce effect on the value of boron atomic absorption. Boron determination limit constituted 0.02 mg/cm 3 for 25 ml of solution introduced

  14. Multisample conversion of water to hydrogen by zinc for stable isotope determination

    Science.gov (United States)

    Kendall, C.; Coplen, T.B.

    1985-01-01

    Two techniques for the conversion of water to hydrogen for stable isotope ratio determination have been developed that are especially suited for automated multisample analysis. Both procedures involve reaction of zinc shot with a water sample at 450 ??C. in one method designed for water samples in bottles, the water is put in capillaries and is reduced by zinc in reaction vessels; overall savings in sample preparation labor of 75% have been realized over the standard uranium reduction technique. The second technique is for waters evolved under vacuum and is a sealed-tube method employing 9 mm o.d. quartz tubing. Problems inherent with zinc reduction include surface inhomogeneity of the zinc and exchange of hydrogen both with the zinc and with the glass walls of the vessels. For best results, water/zinc and water/glass surface area ratios of vessels should be kept as large as possible.

  15. Oscillatory water sorption test for determining water uptake behavior in bread crust

    NARCIS (Netherlands)

    Nieuwenhuijzen, N.H. van; Tromp, R.H.; Hamer, R.J.; Vliet, T. van

    2007-01-01

    In this work, water sorption kinetics of bread crust are described using an oscillatory sorption test in combination with a Langmuir type equation. Both kinetic and thermodynamic information could be obtained at the same time. An advantage of applying a Langmuir type equation for a quantitative

  16. DETERMINATION OF ORGANOCHLORINE PESTICIDES IN DRINKING WATERS SAMPLED FROM CLUJ AND HUNEDOARA COUNTIES

    Directory of Open Access Journals (Sweden)

    MARIA-ELISABETA LOVÁSZ

    2011-03-01

    Full Text Available Determination of organochlorine pesticides in drinking waterssampled from Cluj and Hunedoara counties. Pesticides are found scattered indifferent environmental factors (water, air, soil wherefrom they are drawn off byvegetal and animal organisms. Water pollution by pesticides results from the plantprotection products industry and also from massive application of these resourcesin agriculture and other branches of economy. Pesticides can reach surface wateralong with dripping waters and by infiltration may reach the groundwater layers,organochlorine pesticides are most often found in the water sources (dieldrin,endrin, DDT, aldrin, lindane, heptachlor, etc. due to their increased persistence inthe external environment. This study followed up the determination oforganochlorine pesticides in 14 drinking water samples collected from the outputof water treatment plants in Cluj and Hunedoara counties that process surfacewater and deep-water sources. For identification of organochlorine pesticides, thegas chromatographic method after liquid-liquid extraction was used, by a gascromatograph Shimadzu GC 2010 with detector ECD (Electron CaptureDetection. There were not detected higher values than the method detection limit(0.01 μg/l in the drinking water samples collected and analyzed for both totalorganochlorine pesticides and components, which were well below the maximumconcentration admitted by Law 452/2002 regarding drinking water quality. Resultsare correlated with the sanitary protection areas for water sources and with the useof agricultural lands in the area. The solution to reduce risk of pesticides use isecological agriculture , which gains increasingly more ground in Romania too.

  17. 222Rn determination in mineral waters from the Pocos de Caldas Plateau in Brazil

    International Nuclear Information System (INIS)

    Taddei, M.H.T.; Silva, N.C.; Cipriani, M.

    2002-01-01

    It is estimated that 50% of the radioactive effective dose equivalent to man comes from radon and its radioactivity daughters. The main 222 Rn sources are the soils, building materials and potable waters. There is an especial interest in spas waters with high natural radioactivity. It's considered that the use of these waters as drinking waters is a significant radiation exposure factor, and it is worthwhile to assess the consequent dose. Such estimation has been made for the Pocos de Caldas Plateau, which is a region of high natural radioactivity, from volcanic origin, containing several spas (Aguas da Prata, Caldas, Pocos de Caldas and Andradas). The 222 Rn content was determined in 23 spring waters in Pocos de Caldas and neighboring cities. In water sampling, modified Marinelli flasks were used. The determinations were effected with a high resolution gamma ray spectrometer. High concentration variations were observed in the collected mineral waters, the highest values having been found in Fonte Villela's waters, in Aguas da Prata town (926 Bq/l); Grande Hotel's in Caldas Town (420 Bq/l) and COLAB's in Pocos de Caldas region (289 Bq/l). The annual whole body effective dose equivalent estimate for adult due to water ingestion, using the Crowford-Brown's biokinetic model's adult dose conversion factors, was higher than 1 mSv/year in 61% of the analyzed waters. (author)

  18. The use of stable isotopes in quantitative determinations of exogenous water and added ethanol in wines

    Science.gov (United States)

    Magdas, D. A.; Moldovan, Z.; Cristea, G.

    2012-02-01

    The application of oxygen isotope ratios analysis to wine water according to EU regulation no. 822/97 to determine wine's origin and also, the possible water addition to wines, gained great importance in wines authenticity control. In the natural cycle of water isotopic fractionation, during water evaporation process, the water vapors are depleted in heavy isotopes. On the other hand inside the plants take place an isotope enrichment of heavy stable isotopes of water compared with meteoric water due to photosynthesis and plants transpiration. This process makes possible the detection of exogenous water from wines 18O/16O ratios. Carbon isotopic ratios were used to estimate the supplementary addition of ethanol obtained from C4 plants (sugar cane or corn). This work presents the way in which the isotopic fingerprints (δ13C and δ18O) were used to determine the content of exogenous water from wines and the added supplementary ethanol coming from C4 plants. By using this method, the calculated values obtained for the degree of wine adulteration were in a good agreement with the real exogenous percent of water and ethanol from investigated samples.

  19. Underground Pumped Storage Hydropower using abandoned open pit mines: influence of groundwater seepage on the system efficiency

    Science.gov (United States)

    Pujades, Estanislao; Bodeux, Sarah; Orban, Philippe; Dassargues, Alain

    2016-04-01

    Pumped Storage Hydropower (PSH) plants can be used to manage the production of electrical energy according to the demand. These plants allow storing and generating electricity during low and high demand energy periods, respectively. Nevertheless, PSH plants require a determined topography because two reservoirs located at different heights are needed. At sites where PSH plants cannot be constructed due to topography requirements (flat regions), Underground Pumped Storage Hydropower (UPSH) plants can be used to adjust the electricity production. These plants consist in two reservoirs, the upper one is located at the surface (or at shallow depth) while the lower one is underground (or deeper). Abandoned open pit mines can be used as lower reservoirs but these are rarely isolated. As a consequence, UPSH plants will interact with surrounding aquifers exchanging groundwater. Groundwater seepage will modify hydraulic head inside the underground reservoir affecting global efficiency of the UPSH plant. The influence on the plant efficiency caused by the interaction between UPSH plants and aquifers will depend on the aquifer parameters, underground reservoir properties and pumping and injection characteristics. The alteration of the efficiency produced by the groundwater exchanges, which has not been previously considered, is now studied numerically. A set of numerical simulations are performed to establish in terms of efficiency the effects of groundwater exchanges and the optimum conditions to locate an UPSH plant.

  20. Determination of strontium in drinking water and consequences of radioactive elements present in drinking water for human health

    International Nuclear Information System (INIS)

    Rajkovic, M.B.; Stojanovic, M.D.; Pantelic, G.K.; Vuletic, V.V.

    2006-01-01

    In this paper the analysis of strontium and uranium content in drinking water has been done, indirectly, according to the scale which originates from drinking water in water-supply system of the city of Belgrade. Gamaspectrometric analysis showed the presence of free natural radionuclide in low activities. The activity of 90Sr in scale which is 0.72±0.11 Bq/kg was determined by radiochemical. Because of the small quantities of fur in the house heater this activity can be considered as irrelevant, but the accumulation of scale can have intensified influence. In this paper, the analysis of effects of the radioactive isotopes presence (first of all 238U and 235U) in drinking water on human health has been done