WorldWideScience

Sample records for groundwater level network

  1. Forecasting of Groundwater Level using Artificial Neural Network by incorporating river recharge and river bank infiltration

    Directory of Open Access Journals (Sweden)

    Nizar Shamsuddin Mohd Khairul

    2017-01-01

    Full Text Available Groundwater tables forecasting during implemented river bank infiltration (RBI method is important to identify adequate storage of groundwater aquifer for water supply purposes. This study illustrates the development and application of artificial neural networks (ANNs to predict groundwater tables in two vertical wells located in confined aquifer adjacent to the Langat River. ANN model was used in this study is based on the long period forecasting of daily groundwater tables. ANN models were carried out to predict groundwater tables for 1 day ahead at two different geological materials. The input to the ANN models consider of daily rainfall, river stage, water level, stream flow rate, temperature and groundwater level. Two different type of ANNs structure were used to predict the fluctuation of groundwater tables and compared the best forecasting values. The performance of different models structure of the ANN is used to identify the fluctuation of the groundwater table and provide acceptable predictions. Dynamics prediction and time series of the system can be implemented in two possible ways of modelling. The coefficient correlation (R, Mean Square Error (MSE, Root Mean Square Error (RMSE and coefficient determination (R2 were chosen as the selection criteria of the best model. The statistical values for DW1 are 0.8649, 0.0356, 0.01, and 0.748 respectively. While for DW2 the statistical values are 0.7392, 0.0781, 0.0139, and 0.546 respectively. Based on these results, it clearly shows that accurate predictions can be achieved with time series 1-day ahead of forecasting groundwater table and the interaction between river and aquifer can be examine. The findings of the study can be used to assist policy marker to manage groundwater resources by using RBI method.

  2. Application of artificial neural network model for groundwater level forecasting in a river island with artificial influencing factors

    Science.gov (United States)

    Lee, Sanghoon; Yoon, Heesung; Park, Byeong-Hak; Lee, Kang-Kun

    2017-04-01

    Groundwater use has been increased for various purposes like agriculture, industry or drinking water in recent years, the issue related to sustainability on the groundwater use also has been raised. Accordingly, forecasting the groundwater level is of great importance for planning sustainable use of groundwater. In a small island surrounded by the Han River, South Korea, seasonal fluctuation of the groundwater level is characterized by multiple factors such as recharge/discharge event of the Paldang dam, Water Curtain Cultivation (WCC) during the winter season, operation of Groundwater Heat Pump System (GWHP). For a period when the dam operation is only occurred in the study area, a prediction of the groundwater level can be easily achieved by a simple cross-correlation model. However, for a period when the WCC and the GWHP systems are working together, the groundwater level prediction is challenging due to its unpredictable operation of the two systems. This study performed Artificial Neural Network (ANN) model to forecast the groundwater level in the river area reflecting the various predictable/unpredictable factors. For constructing the ANN models, two monitoring wells, YSN1 and YSO8, which are located near the injection and abstraction wells for the GWHP system were selected, respectively. By training with the groundwater level data measured in January 2015 to August 2015, response of groundwater level by each of the surface water level, the WCC and the GWHP system were evaluated. Consequentially, groundwater levels in December 2015 to March 2016 were predicted by ANN models, providing optimal fits in comparison to the observed water levels. This study suggests that the ANN model is a useful tool to forecast the groundwater level in terms of the management of groundwater. Acknowledgement : Financial support was provided by the "R&D Project on Environmental Management of Geologic CO2 Storage" from the KEITI (Project Number: 2014001810003) This research was

  3. Evaluation of groundwater levels in the South Platte River alluvial aquifer, Colorado, 1953-2012, and design of initial well networks for monitoring groundwater levels

    Science.gov (United States)

    Wellman, Tristan

    2015-01-01

    The South Platte River and underlying alluvial aquifer form an important hydrologic resource in northeastern Colorado that provides water to population centers along the Front Range and to agricultural communities across the rural plains. Water is regulated based on seniority of water rights and delivered using a network of administration structures that includes ditches, reservoirs, wells, impacted river sections, and engineered recharge areas. A recent addendum to Colorado water law enacted during 2002-2003 curtailed pumping from thousands of wells that lacked authorized augmentation plans. The restrictions in pumping were hypothesized to increase water storage in the aquifer, causing groundwater to rise near the land surface at some locations. The U.S. Geological Survey (USGS), in cooperation with the Colorado Water Conservation Board and the Colorado Water Institute, completed an assessment of 60 years (yr) of historical groundwater-level records collected from 1953 to 2012 from 1,669 wells. Relations of "high" groundwater levels, defined as depth to water from 0 to 10 feet (ft) below land surface, were compared to precipitation, river discharge, and 36 geographic and administrative attributes to identify natural and human controls in areas with shallow groundwater.

  4. Optimisation of groundwater level monitoring networks using geostatistical modelling based on the Spartan family variogram and a genetic algorithm method

    Science.gov (United States)

    Parasyris, Antonios E.; Spanoudaki, Katerina; Kampanis, Nikolaos A.

    2016-04-01

    Groundwater level monitoring networks provide essential information for water resources management, especially in areas with significant groundwater exploitation for agricultural and domestic use. Given the high maintenance costs of these networks, development of tools, which can be used by regulators for efficient network design is essential. In this work, a monitoring network optimisation tool is presented. The network optimisation tool couples geostatistical modelling based on the Spartan family variogram with a genetic algorithm method and is applied to Mires basin in Crete, Greece, an area of high socioeconomic and agricultural interest, which suffers from groundwater overexploitation leading to a dramatic decrease of groundwater levels. The purpose of the optimisation tool is to determine which wells to exclude from the monitoring network because they add little or no beneficial information to groundwater level mapping of the area. Unlike previous relevant investigations, the network optimisation tool presented here uses Ordinary Kriging with the recently-established non-differentiable Spartan variogram for groundwater level mapping, which, based on a previous geostatistical study in the area leads to optimal groundwater level mapping. Seventy boreholes operate in the area for groundwater abstraction and water level monitoring. The Spartan variogram gives overall the most accurate groundwater level estimates followed closely by the power-law model. The geostatistical model is coupled to an integer genetic algorithm method programmed in MATLAB 2015a. The algorithm is used to find the set of wells whose removal leads to the minimum error between the original water level mapping using all the available wells in the network and the groundwater level mapping using the reduced well network (error is defined as the 2-norm of the difference between the original mapping matrix with 70 wells and the mapping matrix of the reduced well network). The solution to the

  5. Particle swarm optimization based artificial neural network model for forecasting groundwater level in Udupi district

    Science.gov (United States)

    Balavalikar, Supreetha; Nayak, Prabhakar; Shenoy, Narayan; Nayak, Krishnamurthy

    2018-04-01

    The decline in groundwater is a global problem due to increase in population, industries, and environmental aspects such as increase in temperature, decrease in overall rainfall, loss of forests etc. In Udupi district, India, the water source fully depends on the River Swarna for drinking and agriculture purposes. Since the water storage in Bajae dam is declining day-by-day and the people of Udupi district are under immense pressure due to scarcity of drinking water, alternatively depend on ground water. As the groundwater is being heavily used for drinking and agricultural purposes, there is a decline in its water table. Therefore, the groundwater resources must be identified and preserved for human survival. This research proposes a data driven approach for forecasting the groundwater level. The monthly variations in groundwater level and rainfall data in three observation wells located in Brahmavar, Kundapur and Hebri were investigated and the scenarios were examined for 2000-2013. The focus of this research work is to develop an ANN based groundwater level forecasting model and compare with hybrid ANN-PSO forecasting model. The model parameters are tested using different combinations of the data. The results reveal that PSO-ANN based hybrid model gives a better prediction accuracy, than ANN alone.

  6. Comparison of hybrid spectral-decomposition artificial neural network models for understanding climatic forcing of groundwater levels

    Science.gov (United States)

    Abrokwah, K.; O'Reilly, A. M.

    2017-12-01

    Groundwater is an important resource that is extracted every day because of its invaluable use for domestic, industrial and agricultural purposes. The need for sustaining groundwater resources is clearly indicated by declining water levels and has led to modeling and forecasting accurate groundwater levels. In this study, spectral decomposition of climatic forcing time series was used to develop hybrid wavelet analysis (WA) and moving window average (MWA) artificial neural network (ANN) models. These techniques are explored by modeling historical groundwater levels in order to provide understanding of potential causes of the observed groundwater-level fluctuations. Selection of the appropriate decomposition level for WA and window size for MWA helps in understanding the important time scales of climatic forcing, such as rainfall, that influence water levels. Discrete wavelet transform (DWT) is used to decompose the input time-series data into various levels of approximate and details wavelet coefficients, whilst MWA acts as a low-pass signal-filtering technique for removing high-frequency signals from the input data. The variables used to develop and validate the models were daily average rainfall measurements from five National Atmospheric and Oceanic Administration (NOAA) weather stations and daily water-level measurements from two wells recorded from 1978 to 2008 in central Florida, USA. Using different decomposition levels and different window sizes, several WA-ANN and MWA-ANN models for simulating the water levels were created and their relative performances compared against each other. The WA-ANN models performed better than the corresponding MWA-ANN models; also higher decomposition levels of the input signal by the DWT gave the best results. The results obtained show the applicability and feasibility of hybrid WA-ANN and MWA-ANN models for simulating daily water levels using only climatic forcing time series as model inputs.

  7. Comparison of Groundwater Level Models Based on Artificial Neural Networks and ANFIS.

    Science.gov (United States)

    Djurovic, Nevenka; Domazet, Milka; Stricevic, Ruzica; Pocuca, Vesna; Spalevic, Velibor; Pivic, Radmila; Gregoric, Enika; Domazet, Uros

    2015-01-01

    Water table forecasting plays an important role in the management of groundwater resources in agricultural regions where there are drainage systems in river valleys. The results presented in this paper pertain to an area along the left bank of the Danube River, in the Province of Vojvodina, which is the northern part of Serbia. Two soft computing techniques were used in this research: an adaptive neurofuzzy inference system (ANFIS) and an artificial neural network (ANN) model for one-month water table forecasts at several wells located at different distances from the river. The results suggest that both these techniques represent useful tools for modeling hydrological processes in agriculture, with similar computing and memory capabilities, such that they constitute an exceptionally good numerical framework for generating high-quality models.

  8. Comparison of Groundwater Level Models Based on Artificial Neural Networks and ANFIS

    Directory of Open Access Journals (Sweden)

    Nevenka Djurovic

    2015-01-01

    Full Text Available Water table forecasting plays an important role in the management of groundwater resources in agricultural regions where there are drainage systems in river valleys. The results presented in this paper pertain to an area along the left bank of the Danube River, in the Province of Vojvodina, which is the northern part of Serbia. Two soft computing techniques were used in this research: an adaptive neurofuzzy inference system (ANFIS and an artificial neural network (ANN model for one-month water table forecasts at several wells located at different distances from the river. The results suggest that both these techniques represent useful tools for modeling hydrological processes in agriculture, with similar computing and memory capabilities, such that they constitute an exceptionally good numerical framework for generating high-quality models.

  9. Current Status of Groundwater Monitoring Networks in Korea

    OpenAIRE

    Jin-Yong Lee; Kideok D. Kwon

    2016-01-01

    Korea has been operating groundwater monitoring systems since 1996 as the Groundwater Act enacted in 1994 enforces nationwide monitoring. Currently, there are six main groundwater monitoring networks operated by different government ministries with different purposes: National Groundwater Monitoring Network (NGMN), Groundwater Quality Monitoring Network (GQMN), Seawater Intrusion Monitoring Network (SIMN), Rural Groundwater Monitoring Network (RGMN), Subsidiary Groundwater Monitoring Network ...

  10. Arsenic levels in groundwater aquifer

    African Journals Online (AJOL)

    Miodrag Jelic

    resistance (ρ); dielectric constant (ε); magnetic permeability (η); electrochemical activity ..... comprises grey sands of different particle size distribution ..... groundwater: testing pollution mechanisms for sedimentary aquifers in. Bangladesh.

  11. Developing A National Groundwater-Monitoring Network In Korea

    Science.gov (United States)

    Kim, N. J.; Cho, M. J.; Woo, N. C.

    1995-04-01

    Since the 1960's, the groundwater resources of Korea have been developed without a proper regulatory system for monitoring and preservation, resulting in significant source depletion, land subsidence, water contamination, and sea-water intrusion. With the activation of the "Groundwater Law" in June 1994, the government initiated a project to develop a groundwater-monitoring network to describe general groundwater quality, to define its long-term changes, and to identify major factors affecting changes in groundwater quality and yield. In selecting monitoring locations nationwide, criteria considered are 1) spatial distribution, 2) aquifer characteristics of hydrogeologic units, 3) local groundwater flow regime, 4) linkage with surface hydrology observations, 5) site accessibility, and 6) financial situations. A total of 310 sites in 78 small hydrologic basins were selected to compose the monitoring network. Installation of monitoring wells is scheduled to start in 1995 for 15 sites; the remainder are scheduled to be completed by 2001. At each site, a nest of monitoring wells was designed; shallow and deep groundwater will be monitored for water temperature, pH, EC, DO and TDS every month. Water-level fluctuations will also be measured by automatic recorders equipped with pressure transducers. As a next step, the government plans to develop a groundwater-database management system, which could be linked with surface hydrologic data.

  12. Characterisation of fracture network and groundwater preferential ...

    African Journals Online (AJOL)

    2014-03-18

    Mar 18, 2014 ... In this study, we use a new method to present fracture networks and analyse the connectivity of the .... bounded aquifers are currently the most common targets for water supply ... a conceptual model that integrates all of the available data ...... Integrated multi-scale characterization of ground-water flow and.

  13. Prediction of groundwater levels from lake levels and climate data using ANN approach

    OpenAIRE

    Dogan, Ahmet; Demirpence, Husnu; Cobaner, Murat

    2008-01-01

    There are many environmental concerns relating to the quality and quantity of surface and groundwater. It is very important to estimate the quantity of water by using readily available climate data for managing water resources of the natural environment. As a case study an artificial neural network (ANN) methodology is developed for estimating the groundwater levels (upper Floridan aquifer levels) as a function of monthly averaged precipitation, evaporation, and measured levels of Magnolia an...

  14. Current Status of Groundwater Monitoring Networks in Korea

    Directory of Open Access Journals (Sweden)

    Jin-Yong Lee

    2016-04-01

    Full Text Available Korea has been operating groundwater monitoring systems since 1996 as the Groundwater Act enacted in 1994 enforces nationwide monitoring. Currently, there are six main groundwater monitoring networks operated by different government ministries with different purposes: National Groundwater Monitoring Network (NGMN, Groundwater Quality Monitoring Network (GQMN, Seawater Intrusion Monitoring Network (SIMN, Rural Groundwater Monitoring Network (RGMN, Subsidiary Groundwater Monitoring Network (SGMN, and Drinking Water Monitoring Network (DWMN. The Networks have a total of over 3500 monitoring wells and the majority of them are now equipped with automatic data loggers and remote terminal units. Most of the monitoring data are available to the public through internet websites. These Networks have provided scientific data for designing groundwater management plans and contributed to securing the groundwater resource particularly for recent prolonged drought seasons. Each Network, however, utilizes its own well-specifications, probes, and telecommunication protocols with minimal communication with other Networks, and thus duplicate installations of monitoring wells are not uncommon among different Networks. This mini-review introduces the current regulations and the Groundwater Monitoring Networks operated in Korea and provides some suggestions to improve the sustainability of the current groundwater monitoring system in Korea.

  15. Groundwater levels and dolomite - nuisance or necessity

    CSIR Research Space (South Africa)

    Hobbs, PJ

    2008-11-01

    Full Text Available The significance and importance of groundwater level data in a karst environment, whilst acknowledged by geotechnical engineers and engineering geologists, is often not afforded the recognition it deserves. Within the ambit of a geotechnical site...

  16. Why is the Groundwater Level Rising? A Case Study Using HARTT to Simulate Groundwater Level Dynamic.

    Science.gov (United States)

    Yihdego, Yohannes; Danis, Cara; Paffard, Andrew

    2017-12-01

    Groundwater from a shallow unconfined aquifer at a site in coastal New South Wales has been causing recent water logging issues. A trend of rising groundwater level has been anecdotally observed over the last 10 years. It was not clear whether the changes in groundwater levels were solely natural variations within the groundwater system or whether human interference was driving the level up. Time series topographic images revealed significant surrounding land use changes and human modification to the environment of the groundwater catchment. A statistical model utilising HARTT (multiple linear regression hydrograph analysis method) simulated the groundwater level dynamics at five key monitoring locations and successfully showed a trend of rising groundwater level. Utilising hydrogeological input from field investigations, the model successfully simulated the rise in the water table over time to the present day levels, whilst taking into consideration rainfall and land changes. The underlying geological/land conditions were found to be just as significant as the impact of climate variation. The correlation coefficient for the monitoring bores (MB), excluding MB4, show that the groundwater level fluctuation can be explained by the climate variable (rainfall) with the lag time between the atypical rainfall and groundwater level ranging from 4 to 7 months. The low R2 value for MB4 indicates that there are factors missing in the model which are primarily related to human interference. The elevated groundwater levels in the affected area are the result of long term cumulative land use changes, instigated by humans, which have directly resulted in detrimental changes to the groundwater aquifer properties.

  17. Using groundwater levels to estimate recharge

    Science.gov (United States)

    Healy, R.W.; Cook, P.G.

    2002-01-01

    Accurate estimation of groundwater recharge is extremely important for proper management of groundwater systems. Many different approaches exist for estimating recharge. This paper presents a review of methods that are based on groundwater-level data. The water-table fluctuation method may be the most widely used technique for estimating recharge; it requires knowledge of specific yield and changes in water levels over time. Advantages of this approach include its simplicity and an insensitivity to the mechanism by which water moves through the unsaturated zone. Uncertainty in estimates generated by this method relate to the limited accuracy with which specific yield can be determined and to the extent to which assumptions inherent in the method are valid. Other methods that use water levels (mostly based on the Darcy equation) are also described. The theory underlying the methods is explained. Examples from the literature are used to illustrate applications of the different methods.

  18. The study of using earth tide response of groundwater level and rainfall recharge to identify groundwater aquifer

    Science.gov (United States)

    Huang, W. J.; Hsu, C. H.; Chang, L. C.; Chiang, C. J.; Wang, Y. S.; Lu, W. C.

    2017-12-01

    Hydrogeological framework is the most important basis for groundwater analysis and simulation. Conventionally, the core drill is a most commonly adopted skill to acquire the core's data with the help of other research methods to artificially determine the result. Now, with the established groundwater station network, there are a lot of groundwater level information available. Groundwater level is an integrated presentation of the hydrogeological framework and the external pumping and recharge system. Therefore, how to identify the hydrogeological framework from a large number of groundwater level data is an important subject. In this study, the frequency analysis method and rainfall recharge mechanism were used to identify the aquifer where the groundwater level's response frequency and amplitude react to the earth tide. As the earth tide change originates from the gravity caused by the paths of sun and moon, it leads to soil stress and strain changes, which further affects the groundwater level. The scale of groundwater level's change varies with the influence of aquifer pressure systems such as confined or unconfined aquifers. This method has been applied to the identification of aquifers in the Cho-Shui River Alluvial Fan. The results of the identification are compared to the records of core drill and they both are quite consistent. It is shown that the identification methods developed in this study can considerably contribute to the identification of hydrogeological framework.

  19. Groundwater levels in the Kabul Basin, Afghanistan, 2004-2013

    Science.gov (United States)

    Taher, Mohammad R.; Chornack, Michael P.; Mack, Thomas J.

    2014-01-01

    The Afghanistan Geological Survey, with technical assistance from the U.S. Geological Survey, established a network of wells to measure and monitor groundwater levels to assess seasonal, areal, and potentially climatic variations in groundwater characteristics in the Kabul Basin, Afghanistan, the most populous region in the country. Groundwater levels were monitored in 71 wells in the Kabul Basin, Afghanistan, starting as early as July 2004 and continuing to the present (2013). The monitoring network is made up exclusively of existing production wells; therefore, both static and dynamic water levels were recorded. Seventy wells are in unconsolidated sediments, and one well is in bedrock. Water levels were measured periodically, generally monthly, using electric tape water-level meters. Water levels in well 64 on the grounds of the Afghanistan Geological Survey building were measured more frequently. This report provides a 10-year compilation of groundwater levels in the Kabul Basin prepared in cooperation with the Afghanistan Geological Survey. Depths to water below land surface range from a minimum of 1.47 meters (m) in the Shomali subbasin to a maximum of 73.34 m in the Central Kabul subbasin. The Logar subbasin had the smallest range in depth to water below land surface (1.5 to 12.4 m), whereas the Central Kabul subbasin had the largest range (2.64 to 73.34 m). Seasonal water-level fluctuations can be estimated from the hydrographs in this report for wells that have depth-to-water measurements collected under static conditions. The seasonal water-level fluctuations range from less than 1 m to a little more than 7 m during the monitoring period. In general, the hydrographs for the Deh Sabz, Logar, Paghman and Upper Kabul, and Shomali subbasins show relatively little change in the water-level trend during the period of record, whereas hydrographs for the Central Kabul subbasin show water level decreases of several meters to about 25 m.

  20. Groundwater Level Monitoring using Levelogger and the Importance of Long-Term Groundwater Level Data

    International Nuclear Information System (INIS)

    Nazran Harun; Ahmad Hasnulhadi Che Kamaruddin

    2016-01-01

    This review paper is focused on groundwater level monitoring using levelogger and the importance of long-term groundwater level data. The levelogger provides an inexpensive and convenient method to measure level, temperature and conductivity all in one probe. It can provide real time view as data is being recorded by the connected data logger. Water-level measurements from observation wells are the principal source of information about the hydrologic stresses acting on aquifers and how these stresses affect ground-water recharge, storage, and discharge. Long-term and systematic measurements of water levels provide essential data needed to evaluate changes in the resource over time to develop ground-water models, forecast trends and monitor the effectiveness of groundwater management. A significant advantage of this method of data collection and reporting are the groundwater level data can be updated real time. The accessibility of water level data is greatly enhanced by the Geographic Information System (GIS) to visually illustrate the locations of observation wells relative to relevant topographic, geologic, or hydrologic features. GIS and internet greatly enhance the capability for retrieval and transmittal of water-level data to potential users. (author)

  1. Concentration of Uranium levels in groundwater

    International Nuclear Information System (INIS)

    Babu, M. N. S.; Somashekar, R. K.; Kumar, S. A.; Shivanna, K.; Krishnamurthy, V.; Eappen, K. P.

    2008-01-01

    The uranium isotopes during their course of their disintegration decay into other radioactive elements and eventually decay into stable lead isotopes. The cause of environmental concern is the emanation of beta and gamma radiation during disintegration. The present study tends to estimate uranium in groundwater trapped in granite and gneiss rocks. Besides, the study aims at estimating the radiation during natural disintegration process. The water samples were collected and analyzed following inductively coupled plasma mass spectrometric technique while water sample collection was given to the regions of Kolar District, South India, due to the representation. The significant finding was the observation of very high levels of uranium in groundwater compared to similar assays reported at other nearby districts. Also, the levels were considerable to those compared to groundwater levels of uranium reported by other scientists, On the basis of this study, it was inferred that the origin of uranium was from granite strata and there was a trend of diffusion observed in the course of flow-path of water in the region

  2. Groundwater levels for selected wells in Upper Kittitas County, Washington

    Science.gov (United States)

    Fasser, E.T.; Julich, R.J.

    2011-01-01

    Groundwater levels for selected wells in Upper Kittitas County, Washington, are presented on an interactive, web-based map to document the spatial distribution of groundwater levels in the study area measured during spring 2011. Groundwater-level data and well information were collected by the U.S. Geological Survey using standard techniques and are stored in the U.S. Geological Survey National Water Information System, Groundwater Site-Inventory database.

  3. Will Jakarta Be The Next Atlantis? Excessive Groundwater Use Resulting From A Failing Piped Water Network

    Directory of Open Access Journals (Sweden)

    Nicola Colbran

    2009-06-01

    Full Text Available This article examines the connection between a failing piped water network and excessive groundwater use in Jakarta. It discusses the political history of the city's piped water network, which was privatised in 1998, and how privatisation was intended to increase access to clean, safe water for its residents. The article asserts that this has not eventuated, and that tap water remains costly, unreliable and does not provide noticeable benefits when compared with groundwater. The result is that households, industry, businesses, luxury apartment complexes and hotels choose alternative water sources and distribution methods, in particular groundwater. This is having an unsustainable impact on groundwater levels and Jakarta 's natural environment, causing significant land subsidence, pollution and salinisation of aquifers, and increased levels of flooding. The effect is so severe that the World Bank has predicted much of Jakarta will be inundated by seawater in 2025, rendering one third of the city uninhabitable and displacing millions. The article concludes by discussing and assessing the steps the government has taken to address excessive and unlicensed groundwater use. These steps include new regulations on groundwater, a public awareness campaign on the importance of groundwater and a commitment to improve the raw water supplied to the piped water network. However, the article observes that the government is yet to develop long term policies for improvement of the network itself. The question therefore remains, has the government done enough, or will groundwater use continue unabated making Jakarta the next lost city of Atlantis?

  4. Groundwater level status report for 2010, Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Richard J.; Schmeer, Sarah

    2011-03-01

    The status of groundwater level monitoring at Los Alamos National Laboratory in 2010 is provided in this report. This report summarizes groundwater level data for 194 monitoring wells, including 63 regional aquifer wells (including 10 regional/intermediate wells), 34 intermediate wells, 97 alluvial wells, and 12 water supply wells. Pressure transducers were installed in 162 monitoring wells for continuous monitoring of groundwater levels. Time-series hydrographs of groundwater level data are presented along with pertinent construction and location information for each well. The report also summarizes the groundwater temperatures recorded in intermediate and regional aquifer monitoring wells and seasonal responses to snowmelt runoff observed in intermediate wells.

  5. Groundwater level status report for 2009, Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Richard J.; Schmeer, Sarah

    2010-03-01

    The status of groundwater level monitoring at Los Alamos National Laboratory in 2009 is provided in this report. This report summarizes groundwater level data for 179 monitoring wells, including 55 regional aquifer wells (including 11 regional/intermediate wells), 26 intermediate wells, 98 alluvial wells, and 12 water supply wells. Pressure transducers were installed in 161 monitoring wells for continuous monitoring of groundwater levels. Time-series hydrographs of groundwater level data are presented along with pertinent construction and location information for each well. The report also summarizes the groundwater temperatures recorded in intermediate and regional aquifer monitoring wells.

  6. A combined geostatistical-optimization model for the optimal design of a groundwater quality monitoring network

    Science.gov (United States)

    Kolosionis, Konstantinos; Papadopoulou, Maria P.

    2017-04-01

    Monitoring networks provide essential information for water resources management especially in areas with significant groundwater exploitation due to extensive agricultural activities. In this work, a simulation-optimization framework is developed based on heuristic optimization methodologies and geostatistical modeling approaches to obtain an optimal design for a groundwater quality monitoring network. Groundwater quantity and quality data obtained from 43 existing observation locations at 3 different hydrological periods in Mires basin in Crete, Greece will be used in the proposed framework in terms of Regression Kriging to develop the spatial distribution of nitrates concentration in the aquifer of interest. Based on the existing groundwater quality mapping, the proposed optimization tool will determine a cost-effective observation wells network that contributes significant information to water managers and authorities. The elimination of observation wells that add little or no beneficial information to groundwater level and quality mapping of the area can be obtain using estimations uncertainty and statistical error metrics without effecting the assessment of the groundwater quality. Given the high maintenance cost of groundwater monitoring networks, the proposed tool could used by water regulators in the decision-making process to obtain a efficient network design that is essential.

  7. NEON, Establishing a Standardized Network for Groundwater Observations

    Science.gov (United States)

    Fitzgerald, M.; Schroeter, N.; Goodman, K. J.; Roehm, C. L.

    2013-12-01

    The National Ecological Observatory Network (NEON) is establishing a standardized set of data collection systems comprised of in-situ sensors and observational sampling to obtain data fundamental to the analysis of environmental change at a continental scale. NEON will be collecting aquatic, terrestrial, and atmospheric data using Observatory-wide standardized designs and methods via a systems engineering approach. This approach ensures a wealth of high quality data, data algorithms, and models that will be freely accessible to all communities such as academic researchers, policy makers, and the general public. The project is established to provide 30 years of data which will enable prediction and forecasting of drivers and responses of ecological change at scales ranging from localized responses through regional gradients and up to the continental scale. The Observatory is a distributed system of sites spread across the United States, including Alaska, Hawaii, and Puerto Rico, which is subdivided into 20 statistically unique domains, based on a set of 18 ecologically important parameters. Each domain contains at least one core aquatic and terrestrial site which are located in unmanaged lands, and up to 2 additional sites selected to study domain specific questions such as nitrogen deposition gradients and responses of land use change activities on the ecosystem. Here, we present the development of NEON's groundwater observation well network design and the timing strategy for sampling groundwater chemistry. Shallow well networks, up to 100 feet in depth, will be installed at NEON aquatic sites and will allow for observation of localized ecohydrologic site conditions, by providing basic spatio-temporal near-real time data on groundwater parameters (level, temperature, conductivity) collected from in situ high-resolution instrumentation positioned in each well; and biannual sampling of geochemical and nutrient (N and P) concentrations in a subset of wells for each

  8. Characterizing Groundwater Level and Flow Pattern in a Shallow ...

    African Journals Online (AJOL)

    Bheema

    This study characterize groundwater yield and flow pattern on a shallow ... simple process of weathering, fractured fissure systems, networks of joints and ..... lowest yield in wells that are deeper than the mean well depth in the study area.

  9. Optimizing Groundwater Monitoring Networks Using Integrated Statistical and Geostatistical Approaches

    Directory of Open Access Journals (Sweden)

    Jay Krishna Thakur

    2015-08-01

    Full Text Available The aim of this work is to investigate new approaches using methods based on statistics and geo-statistics for spatio-temporal optimization of groundwater monitoring networks. The formulated and integrated methods were tested with the groundwater quality data set of Bitterfeld/Wolfen, Germany. Spatially, the monitoring network was optimized using geo-statistical methods. Temporal optimization of the monitoring network was carried out using Sen’s method (1968. For geostatistical network optimization, a geostatistical spatio-temporal algorithm was used to identify redundant wells in 2- and 2.5-D Quaternary and Tertiary aquifers. Influences of interpolation block width, dimension, contaminant association, groundwater flow direction and aquifer homogeneity on statistical and geostatistical methods for monitoring network optimization were analysed. The integrated approach shows 37% and 28% redundancies in the monitoring network in Quaternary aquifer and Tertiary aquifer respectively. The geostatistical method also recommends 41 and 22 new monitoring wells in the Quaternary and Tertiary aquifers respectively. In temporal optimization, an overall optimized sampling interval was recommended in terms of lower quartile (238 days, median quartile (317 days and upper quartile (401 days in the research area of Bitterfeld/Wolfen. Demonstrated methods for improving groundwater monitoring network can be used in real monitoring network optimization with due consideration given to influencing factors.

  10. A study of groundwater monitoring data analysis using Artificial Neural Network model

    International Nuclear Information System (INIS)

    Watanabe, Kunio; Gautam, M.R.; Saegusa, Hiromitsu

    2003-05-01

    The results of groundwater flow modeling are to be justified using groundwater monitoring data in the hydrogeological characterization. On the other hand, hydraulic continuities of the geological structures, all of which are considered to have great effect on groundwater flow and/or groundwater quality, are to be estimated using the groundwater flow monitoring data with hydraulic response to some impacts such as borehole drilling, pumping test and so on. Therefore, the groundwater monitoring is important for characterizing the geological and hydrogeological environments. In order to characterize of hydrogeological environment using the monitoring data, it is important to evaluate the influence of artificial and natural impact on the monitoring data. In this study, the following three research works are carried out based on the groundwater monitoring data collected at the Tono area. Artificial Neural Network (ANN) was adopted as the tool for monitoring data analysis. Runoff analysis for assessment of importance of soil moisture on runoff estimation in a catchment. Analysis of water level fluctuation for determination influence factors in the water level fluctuation and for filtering out the influence factors from the water level data . Analysis of hydraulic pressure fluctuation in deep geological formations for hydrogeological characterization and assessment of human influence on the pore pressure in deep formation. Through this study, applicability of ANN for analysis and interpretation of the groundwater monitoring data could be confirmed and methodology for utilization the monitoring data for understanding and characterization of hydrogeological environment could be developed. (author)

  11. Fluctuation patterns of groundwater levels in Tokyo caused by the Great East Japan Earthquake

    Science.gov (United States)

    Kawamura, Akira; Ishihara, Shigeyuki; Amaguchi, Hideo; Takasaki, Tadakatsu

    2016-04-01

    The hourly groundwater levels have been observed at 42 sites in Tokyo Metropolis since 1952. The Great East Japan Earthquake occurred at 14:46 JST on March 11, 2011. It was the strongest earthquake on record with a magnitude of 9.0 (Mw) and large fluctuations of unconfined and confined groundwater levels were observed at 102 observation wells in Tokyo, around 400 km away from the epicenter. Abrupt rises and sharp drawdowns of groundwater levels were observed right after the earthquake for most of the wells, although some did not show a change. In this study, taking full advantage of the unique rare case data from the dense groundwater monitoring network in Tokyo, we investigate the fluctuation patterns of unconfined and confined groundwater levels caused by the Great East Japan Earthquake. The groundwater level data used in this study consist of one month time series in March 2011 with one-hour interval. The fluctuation patterns of groundwater levels caused by the earthquake were identified using Self-Organizing Maps (SOM). The SOM, developed by Kohonen, can project high-dimensional, complex target data onto a two-dimensional regularly arranged map in proportion to the degree of properties. In general, the objective of the SOM application is to obtain useful and informative reference vectors. These vectors can be acquired after iterative updates through the training of the SOM. Design of the SOM structure, selection of a proper initialization method, and data transformation methods were carried out in the SOM application process. The reference vectors obtained from the SOM application were fine-tuned using cluster analysis methods. The optimal number of clusters was selected by the Davies-Bouldin index (DBI) using the k-means algorithm. Using the optimal number of cluster, a final fine-tuning cluster analysis was carried out by Ward's method. As a result, the fluctuation patterns of the confined and unconfined groundwater level were classified into eight clusters

  12. Prediction of monthly regional groundwater levels through hybrid soft-computing techniques

    Science.gov (United States)

    Chang, Fi-John; Chang, Li-Chiu; Huang, Chien-Wei; Kao, I.-Feng

    2016-10-01

    Groundwater systems are intrinsically heterogeneous with dynamic temporal-spatial patterns, which cause great difficulty in quantifying their complex processes, while reliable predictions of regional groundwater levels are commonly needed for managing water resources to ensure proper service of water demands within a region. In this study, we proposed a novel and flexible soft-computing technique that could effectively extract the complex high-dimensional input-output patterns of basin-wide groundwater-aquifer systems in an adaptive manner. The soft-computing models combined the Self Organized Map (SOM) and the Nonlinear Autoregressive with Exogenous Inputs (NARX) network for predicting monthly regional groundwater levels based on hydrologic forcing data. The SOM could effectively classify the temporal-spatial patterns of regional groundwater levels, the NARX could accurately predict the mean of regional groundwater levels for adjusting the selected SOM, the Kriging was used to interpolate the predictions of the adjusted SOM into finer grids of locations, and consequently the prediction of a monthly regional groundwater level map could be obtained. The Zhuoshui River basin in Taiwan was the study case, and its monthly data sets collected from 203 groundwater stations, 32 rainfall stations and 6 flow stations during 2000 and 2013 were used for modelling purpose. The results demonstrated that the hybrid SOM-NARX model could reliably and suitably predict monthly basin-wide groundwater levels with high correlations (R2 > 0.9 in both training and testing cases). The proposed methodology presents a milestone in modelling regional environmental issues and offers an insightful and promising way to predict monthly basin-wide groundwater levels, which is beneficial to authorities for sustainable water resources management.

  13. Application of Artificial Neural Networks to Complex Groundwater Management Problems

    International Nuclear Information System (INIS)

    Coppola, Emery; Poulton, Mary; Charles, Emmanuel; Dustman, John; Szidarovszky, Ferenc

    2003-01-01

    As water quantity and quality problems become increasingly severe, accurate prediction and effective management of scarcer water resources will become critical. In this paper, the successful application of artificial neural network (ANN) technology is described for three types of groundwater prediction and management problems. In the first example, an ANN was trained with simulation data from a physically based numerical model to predict head (groundwater elevation) at locations of interest under variable pumping and climate conditions. The ANN achieved a high degree of predictive accuracy, and its derived state-transition equations were embedded into a multiobjective optimization formulation and solved to generate a trade-off curve depicting water supply in relation to contamination risk. In the second and third examples, ANNs were developed with real-world hydrologic and climate data for different hydrogeologic environments. For the second problem, an ANN was developed using data collected for a 5-year, 8-month period to predict heads in a multilayered surficial and limestone aquifer system under variable pumping, state, and climate conditions. Using weekly stress periods, the ANN substantially outperformed a well-calibrated numerical flow model for the 71-day validation period, and provided insights into the effects of climate and pumping on water levels. For the third problem, an ANN was developed with data collected automatically over a 6-week period to predict hourly heads in 11 high-capacity public supply wells tapping a semiconfined bedrock aquifer and subject to large well-interference effects. Using hourly stress periods, the ANN accurately predicted heads for 24-hour periods in all public supply wells. These test cases demonstrate that the ANN technology can solve a variety of complex groundwater management problems and overcome many of the problems and limitations associated with traditional physically based flow models

  14. Regional Groundwater Flow Assessment in a Prospective High-Level Radioactive Waste Repository of China

    Directory of Open Access Journals (Sweden)

    Xiaoyuan Cao

    2017-07-01

    Full Text Available The production of nuclear energy will result in high-level radioactive waste (HLRW, which brings potential environmental dangers. Selecting a proper disposal repository is a crucial step in the development of nuclear energy. This paper introduces firstly the hydrogeological conditions of the Beishan area in China. Next, a regional groundwater model is constructed using a multiphase flow simulator to analyze the groundwater flow pattern in the Beishan area. Model calibration shows that the simulated and observed hydraulic heads match well, and the simulated regional groundwater flow pattern is similar to the surface flow pattern from the channel network, indicating that the groundwater flow is mainly dependent on the topography. In addition, the simulated groundwater storage over the period from 2003 to 2014 is similar to the trend derived from the Gravity Recovery and Climate Experiment satellite-derived results. Last, the established model is used to evaluate the influences of the extreme climate and regional faults on the groundwater flow pattern. It shows that they do not have a significant influence on the regional groundwater flow patterns. This study will provide a preliminary reference for the regional groundwater flow assessment in the site of the HLRW in China.

  15. Radon levels in a water distribution network

    International Nuclear Information System (INIS)

    Alabdula'aly, A.I.

    1997-01-01

    The capital city of Saudi Arabia, Riyadh, relies on both desalinated sea water as well as treated groundwater to meet all its water requirements. About 66% of the water demand is met by desalinated sea water, and the remaining is supplied by six groundwater treatment plants located in the vicinity of the city and supplied with water from 161 wells. The desalinated sea water is blended with only one plant product water and pumped to the distribution network, whereas the other five plants product water is pumped directly to the network. A study of 222 Rn levels in the city distribution network was carried out in which 89 samples were collected from different locations representing the city districts. All samples have shown low radon levels with an average concentration of 0.2 Bq l -1 and a range values of 0.1-1.0 Bq l -1 . The level of radon in different parts of the network was found to be influenced by the water sources to which they are supplied. The lowest radon levels were observed in districts supplied mostly by desalinated sea water. (Author)

  16. Simulation of shallow groundwater levels: Comparison of a data-driven and a conceptual model

    Science.gov (United States)

    Fahle, Marcus; Dietrich, Ottfried; Lischeid, Gunnar

    2015-04-01

    Despite an abundance of models aimed at simulating shallow groundwater levels, application of such models is often hampered by a lack of appropriate input data. Difficulties especially arise with regard to soil data, which are typically hard to obtain and prone to spatial variability, eventually leading to uncertainties in the model results. Modelling approaches relying entirely on easily measured quantities are therefore an alternative to encourage the applicability of models. We present and compare two models for calculating 1-day-ahead predictions of the groundwater level that are only based on measurements of potential evapotranspiration, precipitation and groundwater levels. The first model is a newly developed conceptual model that is parametrized using the White method (which estimates the actual evapotranspiration on basis of diurnal groundwater fluctuations) and a rainfall-response ratio. Inverted versions of the two latter approaches are then used to calculate the predictions of the groundwater level. Furthermore, as a completely data-driven alternative, a simple feed-forward multilayer perceptron neural network was trained based on the same inputs and outputs. Data of 4 growing periods (April to October) from a study site situated in the Spreewald wetland in North-east Germany were taken to set-up the models and compare their performance. In addition, response surfaces that relate model outputs to combinations of different input variables are used to reveal those aspects in which the two approaches coincide and those in which they differ. Finally, it will be evaluated whether the conceptual approach can be enhanced by extracting knowledge of the neural network. This is done by replacing in the conceptual model the default function that relates groundwater recharge and groundwater level, which is assumed to be linear, by the non-linear function extracted from the neural network.

  17. Tailoring groundwater quality monitoring to vulnerability: a GIS procedure for network design.

    Science.gov (United States)

    Preziosi, E; Petrangeli, A B; Giuliano, G

    2013-05-01

    Monitoring networks aiming to assess the state of groundwater quality and detect or predict changes could increase in efficiency when fitted to vulnerability and pollution risk assessment. The main purpose of this paper is to describe a methodology aiming at integrating aquifers vulnerability and actual levels of groundwater pollution in the monitoring network design. In this study carried out in a pilot area in central Italy, several factors such as hydrogeological setting, groundwater vulnerability, and natural and anthropogenic contamination levels were analyzed and used in designing a network tailored to the monitoring objectives, namely, surveying the evolution of groundwater quality relating to natural conditions as well as to polluting processes active in the area. Due to the absence of an aquifer vulnerability map for the whole area, a proxi evaluation of it was performed through a geographic information system (GIS) methodology, leading to the so called "susceptibility to groundwater quality degradation". The latter was used as a basis for the network density assessment, while water points were ranked by several factors including discharge, actual contamination levels, maintenance conditions, and accessibility for periodical sampling in order to select the most appropriate to the network. Two different GIS procedures were implemented which combine vulnerability conditions and water points suitability, producing two slightly different networks of 50 monitoring points selected out of the 121 candidate wells and springs. The results are compared with a "manual" selection of the points. The applied GIS procedures resulted capable to select the requested number of water points from the initial set, evaluating the most confident ones and an appropriate density. Moreover, it is worth underlining that the second procedure (point distance analysis [PDA]) is technically faster and simpler to be performed than the first one (GRID + PDA).

  18. Real-Time Management of Groundwater Resources Based on Wireless Sensors Networks

    Directory of Open Access Journals (Sweden)

    Qingguo Zhou

    2018-01-01

    Full Text Available Groundwater plays a vital role in the arid inland river basins, in which the groundwater management is critical to the sustainable development of area economy and ecology. Traditional sustainable management approaches are to analyze different scenarios subject to assumptions or to construct simulation–optimization models to obtain optimal strategy. However, groundwater system is time-varying due to exogenous inputs. In this sense, the groundwater management based on static data is relatively outdated. As part of the Heihe River Basin (HRB, which is a typical arid river basin in Northwestern China, the Daman irrigation district was selected as the study area in this paper. First, a simulation–optimization model was constructed to optimize the pumping rates of the study area according to the groundwater level constraints. Three different groundwater level constraints were assigned to explore sustainable strategies for groundwater resources. The results indicated that the simulation–optimization model was capable of identifying the optimal pumping yields and satisfy the given constraints. Second, the simulation–optimization model was integrated with wireless sensors network (WSN technology to provide real-time features for the management. The results showed time-varying feature for the groundwater management, which was capable of updating observations, constraints, and decision variables in real time. Furthermore, a web-based platform was developed to facilitate the decision-making process. This study combined simulation and optimization model with WSN techniques and meanwhile attempted to real-time monitor and manage the scarce groundwater resource, which could be used to support the decision-making related to sustainable management.

  19. Groundwater management based on monitoring of land subsidence and groundwater levels in the Kanto Groundwater Basin, Central Japan

    Science.gov (United States)

    Furuno, K.; Kagawa, A.; Kazaoka, O.; Kusuda, T.; Nirei, H.

    2015-11-01

    Over 40 million people live on and exploit the groundwater resources of the Kanto Plain. The Plain encompasses metropolitan Tokyo and much of Chiba Prefecture. Useable groundwater extends to the base of the Kanto Plain, some 2500 to 3000 m below sea level. Much of the Kanto Plain surface is at sea level. By the early 1970s, with increasing urbanization and industrial expansion, local overdraft of groundwater resources caused major ground subsidence and damage to commercial and residential structures as well as to local and regional infrastructure. Parts of the lowlands around Tokyo subsided to 4.0 m below sea level; particularly affected were the suburbs of Funabashi and Gyotoku in western Chiba. In the southern Kanto Plain, regulations, mainly by local government and later by regional agencies, led to installation of about 500 monitoring wells and almost 5000 bench marks by the 1990's. Many of them are still working with new monitoring system. Long-term monitoring is important. The monitoring systems are costly, but the resulting data provide continuous measurement of the "health" of the Kanto Groundwater Basin, and thus permit sustainable use of the groundwater resource.

  20. Sensitivity of GRACE-derived estimates of groundwater-level changes in southern Ontario, Canada

    Science.gov (United States)

    Hachborn, Ellen; Berg, Aaron; Levison, Jana; Ambadan, Jaison Thomas

    2017-12-01

    Amidst changing climates, understanding the world's water resources is of increasing importance. In Ontario, Canada, low water conditions are currently assessed using only precipitation and watershed-based stream gauges by the Conservation Authorities in Ontario and the Ministry of Natural Resources and Forestry. Regional groundwater-storage changes in Ontario are not currently measured using satellite data by research institutes. In this study, contributions from the Gravity Recovery and Climate Experiment (GRACE) data are compared to a hydrogeological database covering southern Ontario from 2003 to 2013, to determine the suitability of GRACE total water storage estimates for monitoring groundwater storage in this location. Terrestrial water storage data from GRACE were used to determine monthly groundwater storage (GWS) anomaly values. GWS values were also determined by multiplying groundwater-level elevations (from the Provincial Groundwater Monitoring Network wells) by specific yield. Comparisons of GRACE-derived GWS to well-based GWS data determined that GRACE is sufficiently sensitive to obtain a meaningful signal in southern Ontario. Results show that GWS values produced by GRACE are useful for identifying regional changes in groundwater storage in areas with limited available hydrogeological characterization data. Results also indicate that GRACE may have an ability to forecast changes in groundwater storage, which will become useful when monitoring climate shifts in the near future.

  1. Caribbean Sea Level Network

    Science.gov (United States)

    von Hillebrandt-Andrade, C.; Crespo Jones, H.

    2012-12-01

    requirements and factors have been considered for the sustainability of the stations. The sea level stations have to potentially sustain very aggressive conditions of not only tsunamis, but on a more regular basis, hurricanes. Given the requirement that the data be available in near real time, for tsunami and other coastal hazard application, robust communication systems are also essential. For the local operator, the ability to be able to visualize the data is critical and tools like the IOC Sea level Monitoring Facility and the Tide Tool program are very useful. It has also been emphasized the need for these stations to serve multiple purposes. For climate and other research applications the data need to be archived, QC'd and analyzed. Increasing the user base for the sea level data has also been seen as an important goal to gain the local buy in; local weather and meteorological offices are considered as key stakeholders but for whom applications still need to be developed. The CARIBE EWS continues to look forward to working with other IOC partners including the Global Sea Level Observing System (GLOSS) and Sub-Commission for the Caribbean and Adjacent Regions (IOCARIBE)/GOOS, as well as with local, national and global sea level station operators and agencies for the development of a sustainable sea level network.

  2. Characterisation of fracture network and groundwater preferential ...

    African Journals Online (AJOL)

    Characterisation of fractured rocks and evaluation of fracture connectivity are essential for the study of subsurface flow and transport in fractured rock aquifers. In this study, we use a new method to present fracture networks and analyse the connectivity of the fractures, based on the technique of randomly-generated ...

  3. Groundwater dating down to the milliliter level

    International Nuclear Information System (INIS)

    Molnar, M.; Janovics, R.; Rinyu, L.

    2010-01-01

    Complete text of publication follows. A novel method was developed for AMS C-14 measurement of carbonate samples using He carrier gas flushing in septum sealed test tubes. The new and powerful pretreatment method can be applied for normal size (0.1-1.0 mg C) and ultra small size (10-100 μg C) carbonate samples. In this study we investigated the applicability of the new method for dissolved inorganic carbonate (DIC) samples for groundwater radiocarbon analysis. The developed pretreatment method does not require vacuum during sample preparation, which significantly reduces the complexity. Reaction time and conditions can be easily controlled as carbon-dioxide content of water samples is extracted by acid addition in He atmosphere using a simple septum sealed test tube. A double needle with flow controlled He carrier gas is used for CO 2 transfer out from the test tube (Fig. 1). Carbon-dioxide is trapped on a zeolite without using liquid N 2 freezing. The new method can be combined with an automatized graphitization system like AGE from ETHZ giving a full automatizable water preparation line for AMS graphite targets. This case the needed typical sample size is between 5-12 ml of water sample. The most powerful application of the new groundwater pretreatment method is to connect it directly to an AMS using gas ion source interface (Fig.2). With a MICADAS type AMS system we demonstrated that you can routinely measure the C-14 content of 1 ml of water sample with better than 1% precision (for a modern sample). This direct C-14 AMS measurement including sample preparation of one water sample takes about 20 minutes.

  4. Effect of Pumping on Groundwater Levels: A Case Study

    Science.gov (United States)

    Sindhu, G.; Vijayachandran, Lekshmi

    2018-03-01

    Groundwater is a major source for drinking and domestic purposes. Nowadays, extensive pumping has become a major issue of concern since pumping has led to rapid decline in the groundwater table, thus imposing landward gradient, leading to saline water intrusion especially in coastal areas. Groundwater pumping has seen its utmost effect on coastal aquifer systems, where the sea-ward gradient gets disturbed due to anthropogenic influences. Hence, a groundwater flow modelling of an aquifer system is essential for understanding the various hydro-geologic conditions, which can be used to study the responses of the aquifer system with regard to various pumping scenarios. Besides, a model helps to predict the water levels for the future period with respect to changing environment. In this study, a finite element groundwater flow model of a coastal aquifer system at Aakulam, Trivandrum district is developed, calibrated and simulated using the software Finite Element subsurface Flow system (FEFLOW 6.2).This simulated model is then used to predict the groundwater levels for a future 5 year period during pre monsoon and post monsoon season.

  5. Effect of Pumping on Groundwater Levels: A Case Study

    Science.gov (United States)

    Sindhu, G.; Vijayachandran, Lekshmi

    2018-06-01

    Groundwater is a major source for drinking and domestic purposes. Nowadays, extensive pumping has become a major issue of concern since pumping has led to rapid decline in the groundwater table, thus imposing landward gradient, leading to saline water intrusion especially in coastal areas. Groundwater pumping has seen its utmost effect on coastal aquifer systems, where the sea-ward gradient gets disturbed due to anthropogenic influences. Hence, a groundwater flow modelling of an aquifer system is essential for understanding the various hydro-geologic conditions, which can be used to study the responses of the aquifer system with regard to various pumping scenarios. Besides, a model helps to predict the water levels for the future period with respect to changing environment. In this study, a finite element groundwater flow model of a coastal aquifer system at Aakulam, Trivandrum district is developed, calibrated and simulated using the software Finite Element subsurface Flow system (FEFLOW 6.2).This simulated model is then used to predict the groundwater levels for a future 5 year period during pre monsoon and post monsoon season.

  6. Monitoring groundwater: optimising networks to take account of cost effectiveness, legal requirements and enforcement realities

    Science.gov (United States)

    Allan, A.; Spray, C.

    2013-12-01

    The quality of monitoring networks and modeling in environmental regulation is increasingly important. This is particularly true with respect to groundwater management, where data may be limited, physical processes poorly understood and timescales very long. The powers of regulators may be fatally undermined by poor or non-existent networks, primarily through mismatches between the legal standards that networks must meet, actual capacity and the evidentiary standards of courts. For example, in the second and third implementation reports on the Water Framework Directive, the European Commission drew attention to gaps in the standards of mandatory monitoring networks, where the standard did not meet the reality. In that context, groundwater monitoring networks should provide a reliable picture of groundwater levels and a ';coherent and comprehensive' overview of chemical status so that anthropogenically influenced long-term upward trends in pollutant levels can be tracked. Confidence in this overview should be such that 'the uncertainty from the monitoring process should not add significantly to the uncertainty of controlling the risk', with densities being sufficient to allow assessment of the impact of abstractions and discharges on levels in groundwater bodies at risk. The fact that the legal requirements for the quality of monitoring networks are set out in very vague terms highlights the many variables that can influence the design of monitoring networks. However, the quality of a monitoring network as part of the armory of environmental regulators is potentially of crucial importance. If, as part of enforcement proceedings, a regulator takes an offender to court and relies on conclusions derived from monitoring networks, a defendant may be entitled to question those conclusions. If the credibility, reliability or relevance of a monitoring network can be undermined, because it is too sparse, for example, this could have dramatic consequences on the ability of a

  7. Temporal scaling and spatial statistical analyses of groundwater level fluctuations

    Science.gov (United States)

    Sun, H.; Yuan, L., Sr.; Zhang, Y.

    2017-12-01

    Natural dynamics such as groundwater level fluctuations can exhibit multifractionality and/or multifractality due likely to multi-scale aquifer heterogeneity and controlling factors, whose statistics requires efficient quantification methods. This study explores multifractionality and non-Gaussian properties in groundwater dynamics expressed by time series of daily level fluctuation at three wells located in the lower Mississippi valley, after removing the seasonal cycle in the temporal scaling and spatial statistical analysis. First, using the time-scale multifractional analysis, a systematic statistical method is developed to analyze groundwater level fluctuations quantified by the time-scale local Hurst exponent (TS-LHE). Results show that the TS-LHE does not remain constant, implying the fractal-scaling behavior changing with time and location. Hence, we can distinguish the potentially location-dependent scaling feature, which may characterize the hydrology dynamic system. Second, spatial statistical analysis shows that the increment of groundwater level fluctuations exhibits a heavy tailed, non-Gaussian distribution, which can be better quantified by a Lévy stable distribution. Monte Carlo simulations of the fluctuation process also show that the linear fractional stable motion model can well depict the transient dynamics (i.e., fractal non-Gaussian property) of groundwater level, while fractional Brownian motion is inadequate to describe natural processes with anomalous dynamics. Analysis of temporal scaling and spatial statistics therefore may provide useful information and quantification to understand further the nature of complex dynamics in hydrology.

  8. Comparison of selection methods to deduce natural background levels for groundwater units

    NARCIS (Netherlands)

    Griffioen, J.; Passier, H.F.; Klein, J.

    2008-01-01

    Establishment of natural background levels (NBL) for groundwater is commonly performed to serve as reference when assessing the contamination status of groundwater units. We compare various selection methods to establish NBLs using groundwater quality data forfour hydrogeologically different areas

  9. Modeling the Effects of Sea-Level Rise on Groundwater Levels in Coastal New Hampshire

    Science.gov (United States)

    Jacobs, J. M.; Knott, J. F.; Daniel, J.; Kirshen, P. H.

    2017-12-01

    Coastal communities with high population density and low topography are vulnerable from sea-level rise (SLR) caused by climate change. Groundwater in coastal communities will rise with sea level impacting water quality, the structural integrity of infrastructure, and natural ecosystem health. SLR-induced groundwater rise has been studied in areas of high aquifer transmissivity and in low-lying areas immediately along the coast. In this regional study, we investigate SLR-induced groundwater rise in a coastal area characterized by shallow unconsolidated deposits overlying fractured bedrock, typical of the glaciated northeast United States. MODFLOW, a numerical groundwater-flow model, is used with groundwater observations, lidar topography, surface-water hydrology, and groundwater withdrawals to investigate SLR-induced changes in groundwater levels and vadose-zone thickness in New Hampshire's Seacoast. The SLR groundwater signal is detected up to 5 km from the coast, more than 3 times farther inland than projected surface-water flooding associated with SLR. Relative groundwater rise ranges from 38 to 98% of SLR within 1 km of the shoreline and drops below 4% between 4 and 5 km from the coast. The largest magnitude of SLR-induced groundwater rise occurs in the marine and estuarine deposits and land areas with tidal water bodies on three sides. In contrast, groundwater rise is dampened near streams. Groundwater inundation caused by 2 m of SLR is projected to contribute 48% of the total land inundation area in the City of Portsmouth with consequences for built and natural resources. Freshwater wetlands are projected to expand 3% by year 2030 increasing to 25% by year 2100 coupled with water-depth increases. These results imply that underground infrastructure and natural resources in coastal communities will be impacted by rising groundwater much farther inland than previously thought when considering only surface-water flooding from SLR.

  10. Conception to set up a new groundwater monitoring network in Serbia

    Directory of Open Access Journals (Sweden)

    Stevanović Zoran

    2015-01-01

    Full Text Available The Water Framework Directive of the European Union (WFD adopted in year 2000. outlines number of water policy and management actions, where monitoring is of primary importance. Following WFD principles Serbia adopted new legislation in water sector aiming to conserve or achieve good ecological, chemical and quantitative status of water resources. Serbia, as most of the countries of former Yugoslavia mostly uses groundwater for drinking water supply (over 75%. However, the current situation in monitoring of groundwater quality and quantity is far from satisfactory. Several hundred piezometers for observation of groundwater level under auspices of the Hydrometeorological Service of Serbia are located mostly in alluviums of major rivers, while some 70 piezometers are used by the Serbian Environmental Protection Agency for controlling groundwater quality. Currently only 20% of delineated groundwater bodies are under observation. This paper evaluates current conditions and proposes to expand national monitoring network to cover most of groundwater bodies or their groups, to raise number of observation points to a density of ca. 1 object /200 km2 and to include as much as possible actual waterworks in this network. Priority in selecting sites for new observation piezometers or springs has to be given to groundwater bodies under threats, either to their water reserves or their water chemical quality. For the former, an assessment of available renewable reserves versus exploitation capacity is needed, while to estimate pressures on water quality, the best way is to compare aquifers’ vulnerability against anthropogenic (diffuse and punctual hazards. [Projekat Ministarstva nauke Republike Srbije, br. 176022

  11. Risk assessment of groundwater level variability using variable Kriging methods

    Science.gov (United States)

    Spanoudaki, Katerina; Kampanis, Nikolaos A.

    2015-04-01

    Assessment of the water table level spatial variability in aquifers provides useful information regarding optimal groundwater management. This information becomes more important in basins where the water table level has fallen significantly. The spatial variability of the water table level in this work is estimated based on hydraulic head measured during the wet period of the hydrological year 2007-2008, in a sparsely monitored basin in Crete, Greece, which is of high socioeconomic and agricultural interest. Three Kriging-based methodologies are elaborated in Matlab environment to estimate the spatial variability of the water table level in the basin. The first methodology is based on the Ordinary Kriging approach, the second involves auxiliary information from a Digital Elevation Model in terms of Residual Kriging and the third methodology calculates the probability of the groundwater level to fall below a predefined minimum value that could cause significant problems in groundwater resources availability, by means of Indicator Kriging. The Box-Cox methodology is applied to normalize both the data and the residuals for improved prediction results. In addition, various classical variogram models are applied to determine the spatial dependence of the measurements. The Matérn model proves to be the optimal, which in combination with Kriging methodologies provides the most accurate cross validation estimations. Groundwater level and probability maps are constructed to examine the spatial variability of the groundwater level in the basin and the associated risk that certain locations exhibit regarding a predefined minimum value that has been set for the sustainability of the basin's groundwater resources. Acknowledgement The work presented in this paper has been funded by the Greek State Scholarships Foundation (IKY), Fellowships of Excellence for Postdoctoral Studies (Siemens Program), 'A simulation-optimization model for assessing the best practices for the

  12. Plan for a groundwater monitoring network in Taiwan

    Science.gov (United States)

    Hsu, Shiang-Kueen

    In Taiwan, rapid economic growth, rising standards of living, and an altered societal structure have in recent years put severe demands on water supplies. Because of its stable quantity and quality, groundwater has long been a reliable source of water for domestic, agricultural, and industrial users, but the establishment of a management program that integrates groundwater and surface-water use has been hampered by the lack of groundwater data. In 1992, the Department of Water Resources (DWR) initiated a program entitled "Groundwater Monitoring Network Plan in Taiwan." Under this program, basic groundwater data, including water-level and water-quality data, are being collected, and a reliable database is being established for the purpose of managing total water resources. This paper introduces the goals, implementation stages, and scope of that plan. The plan calls for constructing 517 hydrogeologic survey stations and 990 groundwater monitoring wells within 17 years. Under this program, water-level fluctuations are continuously monitored, whereas water-quality samples are taken for analysis only at the initial drilling stage and, subsequently, at the time when a monitoring well is being serviced. In 1996, the DWR and the Water Resources Planning Commission were merged to form today's Water Resources Bureau. Résumé A Taïwan, l'expansion économique rapide, l'amélioration des conditions de vie et la transformation de la structure sociale ont provoqué, ces dernières années, une très forte demande en eau. Du fait de sa constance en qualité et en quantité, l'eau souterraine a longtemps été considérée comme une ressource en eau sûre pour les usages domestiques, agricoles et industriels. Mais la mise en place d'un programme de gestion intégrant les utilisations d'eaux souterraines et de surface a été gênée par l'absence de données sur les eaux souterraines. En 1992, le Département des Ressources en Eau a lancé le programme "Plan pour un réseau de

  13. Simulation of the effects of rainfall and groundwater use on historical lake water levels, groundwater levels, and spring flows in central Florida

    Science.gov (United States)

    O'Reilly, Andrew M.; Roehl, Edwin A.; Conrads, Paul; Daamen, Ruby C.; Petkewich, Matthew D.

    2014-01-01

    The urbanization of central Florida has progressed substantially in recent decades, and the total population in Lake, Orange, Osceola, Polk, and Seminole Counties more than quadrupled from 1960 to 2010. The Floridan aquifer system is the primary source of water for potable, industrial, and agricultural purposes in central Florida. Despite increases in groundwater withdrawals to meet the demand of population growth, recharge derived by infiltration of rainfall in the well-drained karst terrain of central Florida is the largest component of the long-term water balance of the Floridan aquifer system. To complement existing physics-based groundwater flow models, artificial neural networks and other data-mining techniques were used to simulate historical lake water level, groundwater level, and spring flow at sites throughout the area. Historical data were examined using descriptive statistics, cluster analysis, and other exploratory analysis techniques to assess their suitability for more intensive data-mining analysis. Linear trend analyses of meteorological data collected by the National Oceanic and Atmospheric Administration at 21 sites indicate 67 percent of sites exhibited upward trends in air temperature over at least a 45-year period of record, whereas 76 percent exhibited downward trends in rainfall over at least a 95-year period of record. Likewise, linear trend analyses of hydrologic response data, which have varied periods of record ranging in length from 10 to 79 years, indicate that water levels in lakes (307 sites) were about evenly split between upward and downward trends, whereas water levels in 69 percent of wells (out of 455 sites) and flows in 68 percent of springs (out of 19 sites) exhibited downward trends. Total groundwater use in the study area increased from about 250 million gallons per day (Mgal/d) in 1958 to about 590 Mgal/d in 1980 and remained relatively stable from 1981 to 2008, with a minimum of 559 Mgal/d in 1994 and a maximum of 773

  14. Temporal scaling of groundwater level fluctuations near a stream

    Science.gov (United States)

    Schilling, K.E.; Zhang, Y.-K.

    2012-01-01

    Temporal scaling in stream discharge and hydraulic heads in riparian wells was evaluated to determine the feasibility of using spectral analysis to identify potential surface and groundwater interaction. In floodplains where groundwater levels respond rapidly to precipitation recharge, potential interaction is established if the hydraulic head (h) spectrum of riparian groundwater has a power spectral density similar to stream discharge (Q), exhibiting a characteristic breakpoint between high and low frequencies. At a field site in Walnut Creek watershed in central Iowa, spectral analysis of h in wells located 1 m from the channel edge showed a breakpoint in scaling very similar to the spectrum of Q (~20 h), whereas h in wells located 20 and 40 m from the channel showed temporal scaling from 1 to 10,000 h without a well-defined breakpoint. The spectral exponent (??) in the riparian zone decreased systematically from the channel into the floodplain as groundwater levels were increasingly dominated by white noise groundwater recharge. The scaling pattern of hydraulic head was not affected by land cover type, although the number of analyses was limited and site conditions were variable among sites. Spectral analysis would not replace quantitative tracer or modeling studies, but the method may provide a simple means of confirming potential interaction at some sites. ?? 2011, The Author(s). Ground Water ?? 2011, National Ground Water Association.

  15. Spatial modeling for groundwater arsenic levels in North Carolina.

    Science.gov (United States)

    Kim, Dohyeong; Miranda, Marie Lynn; Tootoo, Joshua; Bradley, Phil; Gelfand, Alan E

    2011-06-01

    To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized categories based on rock type and interpreted mode of deposition/emplacement. The geologic transitions from rocks of a primary pyroclastic origin to rocks of volcaniclastic sedimentary origin were designated as polylines. The data were fitted to a left-censored regression model to identify key determinants of arsenic levels in groundwater. A Bayesian spatial random effects model was then developed to capture any spatial patterns in groundwater arsenic residuals into model estimation. Statistical model results indicate (1) wells close to a transition zone or fault are more likely to contain detectible arsenic; (2) welded tuffs and hydrothermal quartz bodies are associated with relatively higher groundwater arsenic concentrations and even higher for those proximal to a pluton; and (3) wells of greater depth are more likely to contain elevated arsenic. This modeling effort informs policy intervention by creating three-dimensional maps of predicted arsenic levels in groundwater for any location and depth in the area.

  16. Spatial Modeling for Groundwater Arsenic Levels in North Carolina

    Science.gov (United States)

    Kim, Dohyeong; Miranda, Marie Lynn; Tootoo, Joshua; Bradley, Phil; Gelfand, Alan E.

    2013-01-01

    To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized categories based on rock type and interpreted mode of deposition/emplacement. The geologic transitions from rocks of a primary pyroclastic origin to rocks of volcaniclastic sedimentary origin were designated as polylines. The data were fitted to a left-censored regression model to identify key determinants of arsenic levels in groundwater. A Bayesian spatial random effects model was then developed to capture any spatial patterns in groundwater arsenic residuals into model estimation. Statistical model results indicate (1) wells close to a transition zone or fault are more likely to contain detectible arsenic; (2) welded tuffs and hydrothermal quartz bodies are associated with relatively higher groundwater arsenic concentrations and even higher for those proximal to a pluton; and (3) wells of greater depth are more likely to contain elevated arsenic. This modeling effort informs policy intervention by creating three-dimensional maps of predicted arsenic levels in groundwater for any location and depth in the area. PMID:21528844

  17. Spatial modeling for groundwater arsenic levels in North Carolina

    Science.gov (United States)

    Kim, D.; Miranda, M.L.; Tootoo, J.; Bradley, P.; Gelfand, A.E.

    2011-01-01

    To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized categories based on rock type and interpreted mode of deposition/emplacement. The geologic transitions from rocks of a primary pyroclastic origin to rocks of volcaniclastic sedimentary origin were designated as polylines. The data were fitted to a left-censored regression model to identify key determinants of arsenic levels in groundwater. A Bayesian spatial random effects model was then developed to capture any spatial patterns in groundwater arsenic residuals into model estimation. Statistical model results indicate (1) wells close to a transition zone or fault are more likely to contain detectible arsenic; (2) welded tuffs and hydrothermal quartz bodies are associated with relatively higher groundwater arsenic concentrations and even higher for those proximal to a pluton; and (3) wells of greater depth are more likely to contain elevated arsenic. This modeling effort informs policy intervention by creating three-dimensional maps of predicted arsenic levels in groundwater for any location and depth in the area. ?? 2011 American Chemical Society.

  18. Groundwater-quality characteristics for the Wyoming Groundwater-Quality Monitoring Network, November 2009 through September 2012

    Science.gov (United States)

    Boughton, Gregory K.

    2014-01-01

    Groundwater samples were collected from 146 shallow (less than or equal to 500 feet deep) wells for the Wyoming Groundwater-Quality Monitoring Network, from November 2009 through September 2012. Groundwater samples were analyzed for physical characteristics, major ions and dissolved solids, trace elements, nutrients and dissolved organic carbon, uranium, stable isotopes of hydrogen and oxygen, volatile organic compounds, and coliform bacteria. Selected samples also were analyzed for gross alpha radioactivity, gross beta radioactivity, radon, tritium, gasoline range organics, diesel range organics, dissolved hydrocarbon gases (methane, ethene, and ethane), and wastewater compounds. Water-quality measurements and concentrations in some samples exceeded numerous U.S. Environmental Protection Agency (EPA) drinking water standards. Physical characteristics and constituents that exceeded EPA Maximum Contaminant Levels (MCLs) in some samples were arsenic, selenium, nitrite, nitrate, gross alpha activity, and uranium. Total coliforms and Escherichia coli in some samples exceeded EPA Maximum Contaminant Level Goals. Measurements of pH and turbidity and concentrations of chloride, sulfate, fluoride, dissolved solids, aluminum, iron, and manganese exceeded EPA Secondary Maximum Contaminant Levels in some samples. Radon concentrations in some samples exceeded the alternative MCL proposed by the EPA. Molybdenum and boron concentrations in some samples exceeded EPA Health Advisory Levels. Water-quality measurements and concentrations also exceeded numerous Wyoming Department of Environmental Quality (WDEQ) groundwater standards. Physical characteristics and constituents that exceeded WDEQ Class I domestic groundwater standards in some samples were measurements of pH and concentrations of chloride, sulfate, dissolved solids, iron, manganese, boron, selenium, nitrite, and nitrate. Measurements of pH and concentrations of chloride, sulfate, dissolved solids, aluminum, iron

  19. Neural Networks Simulation of the Transport of Contaminants in Groundwater

    Directory of Open Access Journals (Sweden)

    Enrico Zio

    2009-12-01

    Full Text Available The performance assessment of an engineered solution for the disposal of radioactive wastes is based on mathematical models of the disposal system response to predefined accidental scenarios, within a probabilistic approach to account for the involved uncertainties. As the most significant potential pathway for the return of radionuclides to the biosphere is groundwater flow, intensive computational efforts are devoted to simulating the behaviour of the groundwater system surrounding the waste deposit, for different values of its hydrogeological parameters and for different evolution scenarios. In this paper, multilayered neural networks are trained to simulate the transport of contaminants in monodimensional and bidimensional aquifers. The results obtained in two case studies indicate that the approximation errors are within the uncertainties which characterize the input data.

  20. The impact of groundwater level on soil seed bank survival

    NARCIS (Netherlands)

    Bekker, RM; Oomes, MJM; Bakker, JP

    Seed longevity of plant species is an important topic in restoration management, and little is known about the effects of environmental conditions on seed survival and longevity under natural conditions. Therefore, the effect of groundwater level on the survival of seeds in the soil seed bank of a

  1. Arsenic levels in groundwater aquifer of the Neoplanta source area ...

    African Journals Online (AJOL)

    As part of a survey on the groundwater aquifer at the Neoplanta source site, standard laboratory analysis of water quality and an electromagnetic geophysical method were used for long-term quantitative and qualitative monitoring of arsenic levels. This study presents only the results of research conducted in the ...

  2. Extreme groundwater levels caused by extreme weather conditions - the highest ever measured groundwater levels in Middle Germany and their management

    Science.gov (United States)

    Reinstorf, F.; Kramer, S.; Koch, T.; Pfützner, B.

    2017-12-01

    Extreme weather conditions during the years 2009 - 2011 in combination with changes in the regional water management led to maximum groundwater levels in large areas of Germany in 2011. This resulted in extensive water logging, with problems especially in urban areas near rivers, where water logging produced huge problems for buildings and infrastructure. The acute situation still exists in many areas and requires the development of solution concepts. Taken the example of the Elbe-Saale-Region in the Federal State of Saxony-Anhalt, were a pilot research project was carried out, the analytical situation, the development of a management tool and the implementation of a groundwater management concept are shown. The central tool is a coupled water budget - groundwater flow model. In combination with sophisticated multi-scale parameter estimation, a high-resolution groundwater level simulation was carried out. A decision support process with an intensive stakeholder interaction combined with high-resolution simulations enables the development of a management concept for extreme groundwater situations in consideration of sustainable and environmentally sound solutions mainly on the base of passive measures.

  3. Recharge signal identification based on groundwater level observations.

    Science.gov (United States)

    Yu, Hwa-Lung; Chu, Hone-Jay

    2012-10-01

    This study applied a method of the rotated empirical orthogonal functions to directly decompose the space-time groundwater level variations and determine the potential recharge zones by investigating the correlation between the identified groundwater signals and the observed local rainfall records. The approach is used to analyze the spatiotemporal process of piezometric heads estimated by Bayesian maximum entropy method from monthly observations of 45 wells in 1999-2007 located in the Pingtung Plain of Taiwan. From the results, the primary potential recharge area is located at the proximal fan areas where the recharge process accounts for 88% of the spatiotemporal variations of piezometric heads in the study area. The decomposition of groundwater levels associated with rainfall can provide information on the recharge process since rainfall is an important contributor to groundwater recharge in semi-arid regions. Correlation analysis shows that the identified recharge closely associates with the temporal variation of the local precipitation with a delay of 1-2 months in the study area.

  4. Groundwater-Surface water interaction in agricultural watershed that encompasses dense network of High Capacity wells

    Science.gov (United States)

    Talib, A.; Desai, A. R.

    2017-12-01

    The Central Sands region of Wisconsin is characterized by productive trout streams, lakes, farmland and forest. However, stream channelization, past wetland drainage, and ground water withdrawals have disrupted the hydrology of this Central Sands region. Climatically driven conditions in last decade (2000-2008) alone are unable to account for the severely depressed water levels. Increased interception and evapotranspiration from afforested areas in central sand Wisconsin may also be culprit for reduced water recharge. Hence, there is need to study the cumulative effects of changing precipitation patterns, groundwater withdrawals, and forest evapotranspiration to improve projections of the future of lake levels and water availability in this region. Here, the SWAT-MODFLOW coupled model approach was applied at large spatio-temporal scale. The coupled model fully integrates a watershed model (SWAT) with a groundwater flow model (MODFLOW). Surface water and ground water flows were simulated integratively at daily time step to estimate the groundwater discharge to the stream network in Central Sands that encompasses high capacity wells. The model was calibrated (2010-2013) and validated (2014-2017) based on streamflow, groundwater extraction, and water table elevation. As the long-term trends in some of the primary drivers is presently ambiguous in Central Sands under future climate, as is the case for total precipitation or timing of precipitation, we relied on a sensitivity student to quantitatively access how primary and secondary drivers may influence future net groundwater recharge. We demonstrate how such an approach could then be coupled with decision-making models to evaluate the effectiveness of groundwater withdrawal policies under a changing climate.

  5. Determination of groundwater abstractions by means of GRACE data and Artificial Neural Networks

    Science.gov (United States)

    Gemitzi, Alexandra; Tsagkarakis, Konstantinos; Lakshmi, Venkat

    2017-04-01

    The EU Water Framework Directive requires for each groundwater body the determination of annual average rates of abstraction from all points providing more than 10m3 per day as well as groundwater level monitoring, so as to ensure that the available groundwater resource is not exceeded by the long-term annual average rate of abstraction. In order to acquire such information in situ observation networks are necessary. However, there are cases, e.g. Greece where WFD monitoring programme has not yet become operational due to bureaucratic, socioeconomic and often political constraints. The present study aims at determining groundwater use at the aquifer scale by using Gravity Recovery and Climate Experiment (GRACE) satellite data coupled with readily available meteorological data. Traditionally, GRACE data have been used at the global and regional scale due to their coarse resolution and the difficulties in disaggregating the various Total Water Storage (TWS) components. Previous works have evaluated the subsurface anomalies (ΔGW), using supplementary data sets and hydrologic modeling results in order to disaggregate GRACE TWS anomalies into their various components. Recent works however, have shown that changes in groundwater storage are dominating the GRACE Total Water Storage (TWS) changes, therefore it was though reasonable to use changes in Grace derived TWS in order to quantify abstractions from a groundwater body. Statistical downscaling was performed using an Artificial Neural Network in the form a Multilayer Perceptron model, in conjunction with local meteorological data. An ensemble of 100 ANNs provided a means of quantifying uncertainty and improving generalization. The methodology was applied in Rhodope area (NE Greece) and proved to be an efficient way of downscaling GRACE data in order to estimate the monthly quantity of water extracted from a certain aquifer. Although our methodology does not aim at estimating abstractions at single points, it manages

  6. Bayesian Belief Network to support conflict analysis for groundwater protection: the case of the Apulia region.

    Science.gov (United States)

    Giordano, Raffaele; D'Agostino, Daniela; Apollonio, Ciro; Lamaddalena, Nicola; Vurro, Michele

    2013-01-30

    Water resource management is often characterized by conflicts, as a result of the heterogeneity of interests associated with a shared resource. Many water conflicts arise on a global scale and, in particular, an increasing level of conflicts can be observed in the Mediterranean basin, characterized by water scarcity. In the present work, in order to assist the conflict analysis process, and thus outline a proper groundwater management, stakeholders were involved in the process and suitable tools were used in a Mediterranean area (the Apulia region, in Italy). In particular, this paper seeks to elicit and structure farmers' mental models influencing their decision over the main water source for irrigation. The more crucial groundwater is for farmers' objectives, the more controversial is the groundwater protection strategy. Bayesian Belief Networks were developed to simulate farmers' behavior with regard to groundwater management and to assess the impacts of protection strategy. These results have been used to calculate the conflict degree in the study area, derived from the introduction of policies for the reduction of groundwater exploitation for irrigation purposes. The less acceptable the policy is, the more likely it is that conflict will develop between farmers and the Regional Authority. The results of conflict analysis were also used to contribute to the debate concerning potential conflict mitigation measures. The approach adopted in this work has been discussed with a number of experts in groundwater management policies and irrigation management, and its main strengths and weaknesses have been identified. Increasing awareness of the existence of potential conflicts and the need to deal with them can be seen as an interesting initial shift in the Apulia region's water management regime, which is still grounded in merely technical approaches. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Influence of irrigation on the level, salinity and flow of groundwater at ...

    African Journals Online (AJOL)

    2010-03-31

    Mar 31, 2010 ... piezometers had to be measured, all readings were taken within 3 days. Water levels were measured to estab- lish the effect of rainfall, drainage and irrigation on the groundwater level. These levels were also used to gener- ate groundwater contour maps and to determine the groundwater flow directions.

  8. Separation of base flow from streamflow using groundwater levels - illustrated for the Pang catchment (UK)

    NARCIS (Netherlands)

    Peters, E.; Lanen, van H.A.J.

    2005-01-01

    A new filter to separate base flow from streamflow has developed that uses observed groundwater levels. To relate the base flow to the observed groundwater levels, a non-linear relation was used. This relation is suitable for unconfined aquifers with deep groundwater levels that do not respond to

  9. Cost Effective Instrumentation for Developing Autonomous Groundwater Monitoring Networks

    Science.gov (United States)

    Viti, T. M.; Garmire, D. G.

    2017-12-01

    Despite a relatively poor understanding of Hawaiian groundwater systems, the State of Hawaii depends almost exclusively on groundwater for its public water supply. Ike Wai, an NSF funded project (EPSCoR Program Award OIA #1557349) at the University of Hawaii, aims to develop new groundwater models for Hawaii's aquifers, including water quality and transport processes. To better understand aquifer properties such as capacity and hydraulic conductivity, we are developing well-monitoring instruments that can autonomously record water parameters such as conductivity, temperature, and hydraulic head level, with sampling frequencies on the order of minutes. We are currently exploring novel methods and materials for solving classical design problems, such as applying dielectric spectroscopy techniques for measuring salinity, and using recycled materials for producing custom cable assemblies. System components are fabricated in house using rapid prototyping (e.g. 3D printing, circuit board milling, and laser cutting), and traditional manufacturing techniques. This approach allows us to produce custom components while minimizing development cost, and maximizing flexibility in the overall system's design.

  10. A Bayesian maximum entropy-based methodology for optimal spatiotemporal design of groundwater monitoring networks.

    Science.gov (United States)

    Hosseini, Marjan; Kerachian, Reza

    2017-09-01

    This paper presents a new methodology for analyzing the spatiotemporal variability of water table levels and redesigning a groundwater level monitoring network (GLMN) using the Bayesian Maximum Entropy (BME) technique and a multi-criteria decision-making approach based on ordered weighted averaging (OWA). The spatial sampling is determined using a hexagonal gridding pattern and a new method, which is proposed to assign a removal priority number to each pre-existing station. To design temporal sampling, a new approach is also applied to consider uncertainty caused by lack of information. In this approach, different time lag values are tested by regarding another source of information, which is simulation result of a numerical groundwater flow model. Furthermore, to incorporate the existing uncertainties in available monitoring data, the flexibility of the BME interpolation technique is taken into account in applying soft data and improving the accuracy of the calculations. To examine the methodology, it is applied to the Dehgolan plain in northwestern Iran. Based on the results, a configuration of 33 monitoring stations for a regular hexagonal grid of side length 3600 m is proposed, in which the time lag between samples is equal to 5 weeks. Since the variance estimation errors of the BME method are almost identical for redesigned and existing networks, the redesigned monitoring network is more cost-effective and efficient than the existing monitoring network with 52 stations and monthly sampling frequency.

  11. Groundwater Levels for Selected Wells in the Chehalis River Basin, Washington

    Science.gov (United States)

    Fasser, E.T.; Julich, R.J.

    2010-01-01

    Groundwater levels for selected wells in the Chehalis River basin, Washington, are presented on an interactive web-based map to document the spatial distribution of groundwater levels in the study area during late summer 2009. Groundwater level data and well information were collected by the U.S. Geological Survey using standard techniques. The data are stored in the USGS National Water Information System (NWIS), Ground-Water Site-Inventory (GWSI) System.

  12. New approach for simulating groundwater flow in discrete fracture network

    Science.gov (United States)

    Fang, H.; Zhu, J.

    2017-12-01

    In this study, we develop a new approach to calculate groundwater flowrate and hydraulic head distribution in two-dimensional discrete fracture network (DFN) where both laminar and turbulent flows co-exist in individual fractures. The cubic law is used to calculate hydraulic head distribution and flow behaviors in fractures where flow is laminar, while the Forchheimer's law is used to quantify turbulent flow behaviors. Reynolds number is used to distinguish flow characteristics in individual fractures. The combination of linear and non-linear equations is solved iteratively to determine flowrates in all fractures and hydraulic heads at all intersections. We examine potential errors in both flowrate and hydraulic head from the approach of uniform flow assumption. Applying the cubic law in all fractures regardless of actual flow conditions overestimates the flowrate when turbulent flow may exist while applying the Forchheimer's law indiscriminately underestimate the flowrate when laminar flows exist in the network. The contrast of apertures of large and small fractures in the DFN has significant impact on the potential errors of using only the cubic law or the Forchheimer's law. Both the cubic law and Forchheimer's law simulate similar hydraulic head distributions as the main difference between these two approaches lies in predicting different flowrates. Fracture irregularity does not significantly affect the potential errors from using only the cubic law or the Forchheimer's law if network configuration remains similar. Relative density of fractures does not significantly affect the relative performance of the cubic law and Forchheimer's law.

  13. High levels of uranium in groundwater of Ulaanbaatar, Mongolia

    Energy Technology Data Exchange (ETDEWEB)

    Nriagu, Jerome, E-mail: stoten@umich.edu [Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, MI 48109 (United States); Nam, Dong-Ha; Ayanwola, Titilayo A. [Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, MI 48109 (United States); Dinh, Hau [College of Literature, Science and Arts, University of Michigan (United States); Erdenechimeg, Erdenebayar; Ochir, Chimedsuren [Department Of Preventive Medicine, School Of Public Health, Health Science University, Mongolia, Ulaanbaatar (Mongolia); Bolormaa, Tsend-Ayush [Central Water Laboratory of Water Supply and Sewerage Authority (USUG), Ulaanbaatar (Mongolia)

    2012-01-01

    Water samples collected from 129 wells in seven of the nine sub-divisions of Ulaanbaatar were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) using Clean Lab methods. The levels of many trace elements were found to be low with the average concentrations (ranges in brackets) being 0.9 (< 0.1-7.9) {mu}g/L for As; 7.7 (0.12-177) {mu}g/L for Mn; 0.2 (< 0.05-1.9) {mu}g/L for Co; 16 (< 0.1-686) {mu}g/L for Zn; 0.7 (< 0.1-1.8) {mu}g/L for Se; < 0.1 (< 0.02-0.69) {mu}g/L for Cd; and 1.3 (< 0.02-32) {mu}g/L for Pb. The levels of uranium were surprisingly elevated (mean, 4.6 {mu}g/L; range < 0.01-57 {mu}g/L), with the values for many samples exceeding the World Health Organization's guideline of 15 {mu}g/L for uranium in drinking water. Local rocks and soils appear to be the natural source of the uranium. The levels of uranium in Ulaanbaatar's groundwater are in the range that has been associated with nephrotoxicity, high blood pressure, bone dysfunction and likely reproductive impairment in human populations. We consider the risk associated with drinking the groundwater with elevated levels of uranium in Ulaanbaatar to be a matter for some public health concern and conclude that the paucity of data on chronic effects of low level exposure is a risk factor for continuing the injury to many people in this city. - Highlights: Black-Right-Pointing-Pointer We analyzed water samples from wells across the city of Ulaanbaatar, Mongolia for total uranium along with arsenic, manganese, cobalt, zinc, selenium, cadmium and lead. Black-Right-Pointing-Pointer We found that compared to other trace metals and metalloids, the levels of uranium were surprisingly elevated with the values for many samples exceeding the World Health Organization's guideline for drinking water. Black-Right-Pointing-Pointer Local rocks and soils appear to be the natural source of the uranium. Black-Right-Pointing-Pointer The health risk associated with drinking the groundwater

  14. Correlation of BTEX levels and toxicity of condensate contaminated groundwater

    International Nuclear Information System (INIS)

    Headley, J.; Goudey, S.; Birkholz, D.; Hardisty, P.

    1995-01-01

    The concentration of BTEX was determined for 60 groundwater samples collected from 6 gas plants in Western Canada, using conventional purge-and-trap GC/MS procedures. The gas plants were selected to cover different types of operations with different amine process chemicals employed for the sweetening of the raw sour-gas condensates. Aliquots of the ground water samples were subjected to toxicity screening tests, specifically, (a) bacterial luminescence (microtox); (b) daphnia mortality and (c) fathead minnow mortality. For the toxicity tests, sample handling procedures were developed to minimize the loss of volatile organics during the experiments. To account for possible losses, the levels of BTEX were monitored at the start and upon completion of these tests. The results indicated that the toxicity of the groundwater was in general, well correlated to the concentration of BTEX (primarily xylene). Approximately 5% of the samples, however, were observed to be toxic although the concentration of BTEX were below the method detection limit (1 microg/1). Thiophenic volatile organics were implicated for the latter. Based on the laboratory results, the remediation of BTEX is expected to correlate with the removal of the toxicity of the groundwater. These findings are of direct relevance to present technologies employed for remediation of ground water at the Sourgas plants

  15. Groundwater Discharge of Legacy Nitrogen to River Networks: Linking Regional Groundwater Models to Streambed Groundwater-Surface Water Exchange and Nitrogen Processing

    Science.gov (United States)

    Barclay, J. R.; Helton, A. M.; Briggs, M. A.; Starn, J. J.; Hunt, A.

    2017-12-01

    Despite years of management, excess nitrogen (N) is a pervasive problem in many aquatic ecosystems. More than half of surface water in the United States is derived from groundwater, and widespread N contamination in aquifers from decades of watershed N inputs suggest legacy N discharging from groundwater may contribute to contemporary N pollution problems in surface waters. Legacy N loads to streams and rivers are controlled by both regional scale flow paths and fine-scale processes that drive N transformations, such as groundwater-surface water exchange across steep redox gradients that occur at stream bed interfaces. Adequately incorporating these disparate scales is a challenge, but it is essential to understanding legacy N transport and making informed management decisions. We developed a regional groundwater flow model for the Farmington River, a HUC-8 basin that drains to the Long Island Sound, a coastal estuary that suffers from elevated N loads despite decades of management, to understand broad patterns of regional transport. To evaluate and refine the regional model, we used thermal infrared imagery paired with vertical temperature profiling to estimate groundwater discharge at the streambed interface. We also analyzed discharging groundwater for multiple N species to quantify fine scale patterns of N loading and transformation via denitrification at the streambed interface. Integrating regional and local estimates of groundwater discharge of legacy N to river networks should improve our ability to predict spatiotemporal patterns of legacy N loading to and transformation within surface waters.

  16. Validation on groundwater flow model including sea level change. Modeling on groundwater flow in coastal granite area

    International Nuclear Information System (INIS)

    Hasegawa, Takuma; Miyakawa, Kimio

    2009-01-01

    It is important to verify the groundwater flow model that reproduces pressure head, water chemistry, and groundwater age. However, water chemistry and groundwater age are considered to be influenced by historical events. In this study, sea level change during glacial-interglacial cycle was taken into account for simulating salinity and groundwater age at coastal granite area. As a result of simulation, salinity movement could not catch up with sea level changes, and mixing zone was formed below the fresh-water zone. This mixing zone was observed in the field measurement, and the observed salinities were agreed with simulated results including sea level change. The simulated residence time including sea level change is one-tenth of steady state. The reason is that the saline water was washed out during regression and modern sea-water was infiltrated during transgression. As mentioned before, considering sea level change are important to reproduce salinity and helium age at coastal area. (author)

  17. Predicting groundwater level fluctuations with meteorological effect implications—A comparative study among soft computing techniques

    Science.gov (United States)

    Shiri, Jalal; Kisi, Ozgur; Yoon, Heesung; Lee, Kang-Kun; Hossein Nazemi, Amir

    2013-07-01

    The knowledge of groundwater table fluctuations is important in agricultural lands as well as in the studies related to groundwater utilization and management levels. This paper investigates the abilities of Gene Expression Programming (GEP), Adaptive Neuro-Fuzzy Inference System (ANFIS), Artificial Neural Networks (ANN) and Support Vector Machine (SVM) techniques for groundwater level forecasting in following day up to 7-day prediction intervals. Several input combinations comprising water table level, rainfall and evapotranspiration values from Hongcheon Well station (South Korea), covering a period of eight years (2001-2008) were used to develop and test the applied models. The data from the first six years were used for developing (training) the applied models and the last two years data were reserved for testing. A comparison was also made between the forecasts provided by these models and the Auto-Regressive Moving Average (ARMA) technique. Based on the comparisons, it was found that the GEP models could be employed successfully in forecasting water table level fluctuations up to 7 days beyond data records.

  18. HIGH LEVELS OF URANIUM IN GROUNDWATER OF ULAANBAATAR, MONGOLIA

    Science.gov (United States)

    Nriagu, Jerome; Nam, Dong-Ha; Ayanwola, Titilayo A.; Dinh, Hau; Erdenechimeg, Erdenebayar; Ochir, Chimedsuren; Bolormaa, Tsend-Ayush

    2011-01-01

    Water samples collected from 129 wells in seven of the nine sub-divisions of Ulaanbaatar were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) using Clean Lab methods. The levels of many trace elements were found to be very low with the average concentrations (ranges in brackets) being 0.9 (uranium were surprisingly elevated (mean, 4.6 μg/L; range uranium in drinking water. Local rocks and soils appear to be the natural source of the uranium. The levels of uranium in Ulaanbaatar's groundwater are in the range that has been associated with nephrotoxicity, high blood pressure, bone dysfunction and likely reproductive impairment in human populations. We consider the risk associated with drinking the groundwater with elevated levels of uranium in Ulaanbaatar to be a matter for some public health concern and conclude that the paucity of data on chronic effects of low level exposure is a risk factor for continuing the injury to many people in this city. PMID:22142646

  19. Groundwater modelling for fractured and porous media: HYDROCOIN Level 1

    International Nuclear Information System (INIS)

    Noy, D.J.

    1986-01-01

    The report describes work carried out as part of the 'Hydrocoin' project to verify some of the models used by the British Geological Survey on its radioactive waste disposal programme. The author's work on Hydrocoin Level 1 concerned groundwater modelling for fractured and porous media. The overall conclusions arising from the work were: a) pressure fields in saturated media can be reliably calculated by existing programmes, b) three techniques for deriving the flow fields are described, and c) severe practical limitations exist as to the ability of current programs to model variably saturated conditions over moderate distances. (U.K.)

  20. Response of groundwater level and surface-water/groundwater interaction to climate variability: Clarence-Moreton Basin, Australia

    Science.gov (United States)

    Cui, Tao; Raiber, Matthias; Pagendam, Dan; Gilfedder, Mat; Rassam, David

    2018-03-01

    Understanding the response of groundwater levels in alluvial and sedimentary basin aquifers to climatic variability and human water-resource developments is a key step in many hydrogeological investigations. This study presents an analysis of groundwater response to climate variability from 2000 to 2012 in the Queensland part of the sedimentary Clarence-Moreton Basin, Australia. It contributes to the baseline hydrogeological understanding by identifying the primary groundwater flow pattern, water-level response to climate extremes, and the resulting dynamics of surface-water/groundwater interaction. Groundwater-level measurements from thousands of bores over several decades were analysed using Kriging and nonparametric trend analysis, together with a newly developed three-dimensional geological model. Groundwater-level contours suggest that groundwater flow in the shallow aquifers shows local variations in the close vicinity of streams, notwithstanding general conformance with topographic relief. The trend analysis reveals that climate variability can be quickly reflected in the shallow aquifers of the Clarence-Moreton Basin although the alluvial aquifers have a quicker rainfall response than the sedimentary bedrock formations. The Lockyer Valley alluvium represents the most sensitively responding alluvium in the area, with the highest declining (-0.7 m/year) and ascending (2.1 m/year) Sen's slope rates during and after the drought period, respectively. Different surface-water/groundwater interaction characteristics were observed in different catchments by studying groundwater-level fluctuations along hydrogeologic cross-sections. The findings of this study lay a foundation for future water-resource management in the study area.

  1. Ground-water levels and quality data for Georgia

    Science.gov (United States)

    ,

    1979-01-01

    This report begins a publication format that will present annually both water-level and water-quality data in Georgia. In this format the information is presented in two-page units: the left page includes text which summarizes the information for an area or subject and the right page consists of one or more illustrations. Daily mean water-level fluctuations and trends are shown in hydrographs for the previous year and fluctuations for the monthly mean water level the previous 10 years for selected observation wells. The well data best illustrate the effects of changes in recharge and discharge in the various ground-water reservoirs in the State. A short narrative explains fluctuations and trends in each hydrograph. (Woodard-USGS)

  2. Regulatory requirements for groundwater monitoring networks at hazardous waste sites

    International Nuclear Information System (INIS)

    Keller, J.F.

    1989-10-01

    In the absence of an explicit national mandate to protect groundwater quality, operators of active and inactive hazardous waste sites must use a number of statutes and regulations as guidance for detecting, correcting, and preventing groundwater contamination. The objective of this paper is to provide a framework of the technical and regulatory considerations that are important to the development of groundwater monitoring programs at hazardous waste sites. The technical site-specific needs and regulatory considerations, including existing groundwater standards and classifications, will be presented. 14 refs., 2 tabs

  3. Using Geoscience and Geostatistics to Optimize Groundwater Monitoring Networks at the Savannah River Site

    International Nuclear Information System (INIS)

    Tuckfield, R.C.

    2001-01-01

    A team of scientists, engineers, and statisticians was assembled to review the operation efficiency of groundwater monitoring networks at US Department of Energy Savannah River Site (SRS). Subsequent to a feasibility study, this team selected and conducted an analysis of the A/M area groundwater monitoring well network. The purpose was to optimize the number of groundwater wells requisite for monitoring the plumes of the principal constituent of concern, viz., trichloroethylene (TCE). The project gathered technical expertise from the Savannah River Technology Center (SRTC), the Environmental Restoration Division (ERD), and the Environmental Protection Department (EPD) of SRS

  4. Analysis and integrated modelling of groundwater infiltration to sewer networks

    DEFF Research Database (Denmark)

    Thorndahl, Søren Liedtke; Balling, Jonas Dueholm; Larsen, Uffe Bay Bøgh

    2016-01-01

    Infiltration of groundwater to sewer systems is a problem for the capacity of the system as well as for treatment processes at waste water treatment plants. This paper quantifies the infiltration of groundwater to a sewer system in Frederikshavn Municipality, Denmark, by measurements of sewer flo...

  5. A quantitative method for groundwater surveillance monitoring network design at the Hanford Site

    International Nuclear Information System (INIS)

    Meyer, P.D.

    1993-12-01

    As part of the Environmental Surveillance Program at the Hanford Site, mandated by the US Department of Energy, hundreds of groundwater wells are sampled each year, with each sample typically analyzed for a variety of constituents. The groundwater sampling program must satisfy several broad objectives. These objectives include an integrated assessment of the condition of groundwater and the identification and quantification of existing, emerging, or potential groundwater problems. Several quantitative network desip objectives are proposed and a mathematical optimization model is developed from these objectives. The model attempts to find minimum cost network alternatives that maximize the amount of information generated by the network. Information is measured both by the rats of change with respect to time of the contaminant concentration and the uncertainty in contaminant concentration. In an application to tritium monitoring at the Hanford Site, both information measures were derived from historical data using time series analysis

  6. Investigation of the Effect of Water Removal from Wells Surrounding Parishan Lake on Groundwater and Surface Water Levels

    International Nuclear Information System (INIS)

    Shafiei, M.; Raini Sarjaz, M.; Fazloli, R.; Gholami Sefidkouhi, M. A.

    2017-01-01

    In recent decades the human impacts on global warming and, its consequences, climate change, stirred up earth ecosystems balance and has created many problems all over the world. Unauthorized underground water removal, especially in arid and semi-arid regions of Iran, along with recent decade drought occurrences significantly lowered underground and surface water levels. To investigate the impacts of water removal from surrounding wells in Parishan Lake water level, during 1996 to 2009 interval, 8 buffer layers surrounding the lake were mapped in ArcGIS 9.3 environment. Each buffer layer wells and their total annual discharges were determined. Using SPSS 16 software, the regression equations between wells water levels and water discharges were computed. By employing Thiessen function and creating Thiessen network (TIN) around observation wells, decline of groundwater levels was evaluated. Finally regression equations between wells discharges and groundwater level declines were created. The findings showed that there are highly significant correlations (p ≤ 0.01), in all buffer layers, between water levels and wells discharges. Investigation of the observation wells surrounding lake showed that severe groundwater level declines has been started since the beginning of the first decade of the 21st century. Using satellite images in ArcGIS 9.3 environment it was confirmed that lake’s area has been reduced significantly. In conclusion, it is obvious that human interferences on lake’s natural ecosystem by digging unauthorized wells and removing underground water more than annual recharges significantly impacted surface and groundwater levels.

  7. Influences of groundwater extraction on flow dynamics and arsenic levels in the western Hetao Basin, Inner Mongolia, China

    Science.gov (United States)

    Zhang, Zhuo; Guo, Huaming; Zhao, Weiguang; Liu, Shuai; Cao, Yongsheng; Jia, Yongfeng

    2018-04-01

    Data on spatiotemporal variations in groundwater levels are crucial for understanding arsenic (As) behavior and dynamics in groundwater systems. Little is known about the influences of groundwater extraction on the transport and mobilization of As in the Hetao Basin, Inner Mongolia (China), so groundwater levels were recorded in five monitoring wells from 2011 to 2016 and in 57 irrigation wells and two multilevel wells in 2016. Results showed that groundwater level in the groundwater irrigation area had two troughs each year, induced by extensive groundwater extraction, while groundwater levels in the river-diverted (Yellow River) water irrigation area had two peaks each year, resulting from surface-water irrigation. From 2011 to 2016, groundwater levels in the groundwater irrigation area presented a decreasing trend due to the overextraction. Groundwater samples were taken for geochemical analysis each year in July from 2011 to 2016. Increasing trends were observed in groundwater total dissolved solids (TDS) and As. Owing to the reverse groundwater flow direction, the Shahai Lake acts as a new groundwater recharge source. Lake water had flushed the near-surface sediments, which contain abundant soluble components, and increased groundwater salinity. In addition, groundwater extraction induced strong downward hydraulic gradients, which led to leakage recharge from shallow high-TDS groundwater to the deep semiconfined aquifer. The most plausible explanation for similar variations among As, Fe(II) and total organic carbon (TOC) concentrations is the expected dissimilatory reduction of Fe(III) oxyhydroxides.

  8. Groundwater-level trends and implications for sustainable water use in the Kabul Basin, Afghanistan

    Science.gov (United States)

    Mack, Thomas J.; Chornack, Michael P.; Taher, Mohammad R.

    2013-01-01

    The Kabul Basin, which includes the city of Kabul, Afghanistan, with a population of approximately 4 million, has several Afghan, United States, and international military installations that depend on groundwater resources for a potable water supply. This study examined groundwater levels in the Kabul Basin from 2004 to 2012. Groundwater levels have increased slightly in rural areas of the Kabul Basin as a result of normal precipitation after the drought of the early 2000s. However, groundwater levels have decreased in the city of Kabul due to increasing water use in an area with limited recharge. The rate of groundwater-level decrease in the city is greater for the 2008–2012 period (1.5 meters per year (m/yr) on average) than for the 2004–2008 period (0–0.7 m/yr on average). The analysis, which is corroborated by groundwater-flow modeling and a non-governmental organization decision-support model, identified groundwater-level decreases and associated implications for groundwater sustainability in the city of Kabul. Military installations in the city of Kabul (the Central Kabul subbasin) are likely to face water management challenges resulting from long-term groundwater sustainability concerns, such as the potential drying of shallow water-supply wells. Installations in the northern part of the Kabul Basin may have fewer issues with long-term water sustainability. Groundwater-level monitoring and groundwater-flow simulation can be valuable tools for assessing groundwater management options to improve the sustainability of water resources in the Kabul Basin.

  9. Modelling impacts of acid deposition and groundwater level on habitat quality and plant species diversity

    NARCIS (Netherlands)

    Kros, J.; Mol, J.P.; Wamelink, G.W.W.; Reinds, G.J.; Hinsberg, van A.; Vries, de W.

    2016-01-01

    Introduction
    We quantified the effects of the site factors pH and nitrate (NO3) concentration in soil solution and groundwater level on the vegetation of terrestrial ecosystems for the Netherlands in response to changes in atmospheric nitrogen (N) and sulphur (S) deposition and groundwater level

  10. Optimal groundwater remediation using artificial neural networks and the genetic algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, Leah L. [Stanford Univ., CA (United States)

    1992-08-01

    An innovative computational approach for the optimization of groundwater remediation is presented which uses artificial neural networks (ANNs) and the genetic algorithm (GA). In this approach, the ANN is trained to predict an aspect of the outcome of a flow and transport simulation. Then the GA searches through realizations or patterns of pumping and uses the trained network to predict the outcome of the realizations. This approach has advantages of parallel processing of the groundwater simulations and the ability to ``recycle`` or reuse the base of knowledge formed by these simulations. These advantages offer reduction of computational burden of the groundwater simulations relative to a more conventional approach which uses nonlinear programming (NLP) with a quasi-newtonian search. Also the modular nature of this approach facilitates substitution of different groundwater simulation models.

  11. Optimal groundwater remediation using artificial neural networks and the genetic algorithm

    International Nuclear Information System (INIS)

    Rogers, L.L.

    1992-08-01

    An innovative computational approach for the optimization of groundwater remediation is presented which uses artificial neural networks (ANNs) and the genetic algorithm (GA). In this approach, the ANN is trained to predict an aspect of the outcome of a flow and transport simulation. Then the GA searches through realizations or patterns of pumping and uses the trained network to predict the outcome of the realizations. This approach has advantages of parallel processing of the groundwater simulations and the ability to ''recycle'' or reuse the base of knowledge formed by these simulations. These advantages offer reduction of computational burden of the groundwater simulations relative to a more conventional approach which uses nonlinear programming (NLP) with a quasi-newtonian search. Also the modular nature of this approach facilitates substitution of different groundwater simulation models

  12. Seasonal forecasting of groundwater levels in natural aquifers in the United Kingdom

    Science.gov (United States)

    Mackay, Jonathan; Jackson, Christopher; Pachocka, Magdalena; Brookshaw, Anca; Scaife, Adam

    2014-05-01

    Groundwater aquifers comprise the world's largest freshwater resource and provide resilience to climate extremes which could become more frequent under future climate changes. Prolonged dry conditions can induce groundwater drought, often characterised by significantly low groundwater levels which may persist for months to years. In contrast, lasting wet conditions can result in anomalously high groundwater levels which result in flooding, potentially at large economic cost. Using computational models to produce groundwater level forecasts allows appropriate management strategies to be considered in advance of extreme events. The majority of groundwater level forecasting studies to date use data-based models, which exploit the long response time of groundwater levels to meteorological drivers and make forecasts based only on the current state of the system. Instead, seasonal meteorological forecasts can be used to drive hydrological models and simulate groundwater levels months into the future. Such approaches have not been used in the past due to a lack of skill in these long-range forecast products. However systems such as the latest version of the Met Office Global Seasonal Forecast System (GloSea5) are now showing increased skill up to a 3-month lead time. We demonstrate the first groundwater level ensemble forecasting system using a multi-member ensemble of hindcasts from GloSea5 between 1996 and 2009 to force 21 simple lumped conceptual groundwater models covering most of the UK's major aquifers. We present the results from this hindcasting study and demonstrate that the system can be used to forecast groundwater levels with some skill up to three months into the future.

  13. Assessing the suitability of extreme learning machines (ELM for groundwater level prediction

    Directory of Open Access Journals (Sweden)

    Yadav Basant

    2017-03-01

    Full Text Available Fluctuation of groundwater levels around the world is an important theme in hydrological research. Rising water demand, faulty irrigation practices, mismanagement of soil and uncontrolled exploitation of aquifers are some of the reasons why groundwater levels are fluctuating. In order to effectively manage groundwater resources, it is important to have accurate readings and forecasts of groundwater levels. Due to the uncertain and complex nature of groundwater systems, the development of soft computing techniques (data-driven models in the field of hydrology has significant potential. This study employs two soft computing techniques, namely, extreme learning machine (ELM and support vector machine (SVM to forecast groundwater levels at two observation wells located in Canada. A monthly data set of eight years from 2006 to 2014 consisting of both hydrological and meteorological parameters (rainfall, temperature, evapotranspiration and groundwater level was used for the comparative study of the models. These variables were used in various combinations for univariate and multivariate analysis of the models. The study demonstrates that the proposed ELM model has better forecasting ability compared to the SVM model for monthly groundwater level forecasting.

  14. Groundwater-level data from an earthen dam site in southern Westchester County, New York

    Science.gov (United States)

    Noll, Michael L.; Chu, Anthony

    2018-05-01

    In 2005, the U.S. Geological Survey began a cooperative study with New York City Department of Environmental Protection to characterize the local groundwater-flow system and identify potential sources of seeps on the southern embankment of the Hillview Reservoir in Westchester County, New York. Groundwater levels were collected at 49 wells at Hillview Reservoir, and 1 well in northern Bronx County, from April 2005 through November 2016. Groundwater levels were measured discretely with a chalked steel or electric tape, or continuously with a digital pressure transducer, or both, in accordance with U.S. Geological Survey groundwatermeasurement standards. These groundwater-level data were plotted as time series and are presented in this report as hydrographs. Twenty-eight of the 50 hydrographs have continuous record and discrete field groundwater-level measurements, 22 of the hydrographs contain only discrete measurements.

  15. Design of a groundwater sampling network for Minnesota

    International Nuclear Information System (INIS)

    Kanivetsky, R.

    1977-01-01

    This folio was compiled to facilitate the use of groundwater as a sampling medium to aid in exploration for hitherto undiscovered deposits of uranium in the subsurface rocks of Minnesota. The report consists of the following sheets of the hydrogeologic map of Minnesota: (1) map of bedrock hydrogeology, (2) generalized cross sections of the hydrogeologic map of Minnesota, showing both Quaternary deposits and bedrock, (3) map of waterwells that penetrate Precambrian rocks in Minnesota. A list of these wells, showing locations, names of owners, type of Precambrian aquifers penetrated, lithologic material of the aquifers, and well depths is provided in the appendix to this report. Structural settings, locations, and composition of the bedrock aquifers, movement of groundwater, and preliminary suggestions for a sampling program are discussed below under the heading Bedrock Hydrogeology of Minnesota. The map sheet showing Quaternary hydrogeology is not included in this report because the chemistry of groundwater in these deposits is not directly related to bedrock mineralization

  16. Effects of Sea Level Rise on Groundwater Flow Paths in a Coastal Aquifer System

    Science.gov (United States)

    Morrissey, S. K.; Clark, J. F.; Bennett, M. W.; Richardson, E.; Stute, M.

    2008-05-01

    Changes in groundwater flow in the Floridan aquifer system, South Florida, from the rise in sea level at the end of the last glacial period may be indicative of changes coastal aquifers will experience with continued sea level rise. As sea level rises, the hydraulic head near the coast increases. Coastal aquifers can therefore experience decreased groundwater gradients (increased residence times) and seawater intrusion. Stable isotopes of water, dissolved noble gas temperatures, radiocarbon and He concentrations were analyzed in water collected from 68 wells in the Floridan aquifer system throughout South Florida. Near the recharge area, geochemical data along groundwater flow paths in the Upper Floridan aquifer show a transition from recently recharged groundwater to glacial-aged water. Down gradient from this transition, little variation is apparent in the stable isotopes and noble gas recharge temperatures, indicating that most of the Upper Floridan aquifer contains groundwater recharged during the last glacial period. The rapid 120-meter rise in sea level marking the end of the last glacial period increased the hydraulic head in the Floridan aquifer system near the coast, slowing the flow of groundwater from the recharge area to the ocean and trapping glacial-aged groundwater. The raised sea level also flooded half of the Florida platform and caused seawater to intrude into the Lower Floridan. This circulation of seawater in the Lower Floridan continues today as our data indicate that the groundwater is similar to modern seawater with a freshwater component entering vertically from the recharge area to the Upper Floridan.

  17. Past and future contribution of global groundwater depletion to sea-level rise

    NARCIS (Netherlands)

    Wada, Y.; Beek, L.P.H. van; Sperna Weiland, F.C.; Chao, B.; Wu, Y.-H.; Bierkens, M.F.P.

    2012-01-01

    Recent studies suggest the increasing contribution of groundwater depletion to global sea-level rise. Groundwater depletion has more than doubled during the last decades, primarily due to increase in water demand, while the increase in water impoundments behind dams has been tapering off since

  18. Study on the Variation of Groundwater Level under Time-varying Recharge

    Science.gov (United States)

    Wu, Ming-Chang; Hsieh, Ping-Cheng

    2017-04-01

    The slopes of the suburbs come to important areas by focusing on the work of soil and water conservation in recent years. The water table inside the aquifer is affected by rainfall, geology and topography, which will result in the change of groundwater discharge and water level. Currently, the way to obtain water table information is to set up the observation wells; however, owing to that the cost of equipment and the wells excavated is too expensive, we develop a mathematical model instead, which might help us to simulate the groundwater level variation. In this study, we will discuss the groundwater level change in a sloping unconfined aquifer with impermeable bottom under time-varying rainfall events. Referring to Child (1971), we employ the Boussinesq equation as the governing equation, and apply the General Integral Transforms Method (GITM) to analyzing the groundwater level after linearizing the Boussinesq equation. After comparing the solution with Verhoest & Troch (2000) and Bansal & Das (2010), we get satisfactory results. To sum up, we have presented an alternative approach to solve the linearized Boussinesq equation for the response of groundwater level in a sloping unconfined aquifer. The present analytical results combine the effect of bottom slope and the time-varying recharge pattern on the water table fluctuations. Owing to the limitation and difficulty of measuring the groundwater level directly, we develop such a mathematical model that we can predict or simulate the variation of groundwater level affected by any rainfall events in advance.

  19. Development of a model to simulate groundwater inundation induced by sea-level rise and high tides in Honolulu, Hawaii.

    Science.gov (United States)

    Habel, Shellie; Fletcher, Charles H; Rotzoll, Kolja; El-Kadi, Aly I

    2017-05-01

    Many of the world's largest cities face risk of sea-level rise (SLR) induced flooding owing to their limited elevations and proximities to the coastline. Within this century, global mean sea level is expected to reach magnitudes that will exceed the ground elevation of some built infrastructure. The concurrent rise of coastal groundwater will produce additional sources of inundation resulting from narrowing and loss of the vertical unsaturated subsurface space. This has implications for the dense network of buried and low-lying infrastructure that exists across urban coastal zones. Here, we describe a modeling approach that simulates narrowing of the unsaturated space and groundwater inundation (GWI) generated by SLR-induced lifting of coastal groundwater. The methodology combines terrain modeling, groundwater monitoring, estimation of tidal influence, and numerical groundwater-flow modeling to simulate future flood scenarios considering user-specified tide stages and magnitudes of SLR. We illustrate the value of the methodology by applying it to the heavily urbanized and low-lying Waikiki area of Honolulu, Hawaii. Results indicate that SLR of nearly 1 m generates GWI across 23% of the 13 km 2 study area, threatening $5 billion of taxable real estate and 48 km of roadway. Analysis of current conditions reveals that 86% of 259 active cesspool sites in the study area are likely inundated. This suggests that cesspool effluent is currently entering coastal groundwater, which not only leads to degradation of coastal environments, but also presents a future threat to public health as GWI would introduce effluent at the ground surface. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Treatment of groundwater contaminated with low levels of military munitions

    International Nuclear Information System (INIS)

    Bricka, R.M.; Sharp, W.

    1993-01-01

    The site of interest is a military base that was established in the late 1800s. In its early history this facility was used as a powder depot to fill projectiles with miximite (a propellant). Since World War I, this facility was used to produce artillery ammunition, bombs, high explosives, pyrotechnics and other ordinances. Weapons production at this facility has ceased, but as a result of the past activities at this facility, contaminants are migrating into the groundwater. One source of drinking water for this installation is a screened well in a stratified-drift aquifer system at a depth of 75-85 feet below land surface. In the 1980s sampling of this well revealed low level contamination of trichloroethylene (TCE), RDX and HMX. TCE levels exceeded drinking water standards and an air stripping column was installed to remove the TCE. RDX and HMX, concentrations were below drinking water standards. Health Advisory (HA) levels for RDX and HMX were published by the U.S. Environmental Protection Agency (USEPA) in November 1988. The lifetime HA levels are 2 ppb and 400 ppb for RDX and HMX, respectively (McLellan et al. 1988a, and McLellan et al. 1988b). It is expected that continuous withdrawals from this well will increase RDX and HMX concentrations. In addition, it is believed that future USEPA regulations will adapt the HA as a drinking water standard. This study was initiated in an effort to have an appropriate cost effective technology ready to meet any such standard. RDX and HMX RDX and HMX are military explosives. RDX (Hexahydro-l,3,5-trinitro-l,3,5-triazine) is a code name for Research Department Explosive. This explosive is described as a white crystalline solid with about 1.3 times the explosive power of trinitrotoluene (TNT). RDX is classified as a EPA Group C compound: Possible Human Carcinogen (McLellan et. al. 1988a). HMX (Octahydro-1, 3, 5, 7- tetranitro-l, 3, 5, 7-tetrazocine) is a code name for High Melting Explosive. This explosive is described as a

  1. Groundwater reorganization in the Floridan aquifer following Holocene sea-level rise

    OpenAIRE

    Morrissey, SK; Clark, JF; Bennett, M; Richardson, E; Stute, M

    2010-01-01

    Sea-level fluctuations, particularly those associated with glacial-interglacial cycles, can have profound impacts on the flow and circulation of coastal groundwater: the water found at present in many coastal aquifers may have been recharged during the last glacial period, when sea level was over 100 m lower than present, and thus is not in equilibrium with present recharge conditions. Here we show that the geochemistry of the groundwater found in the Floridan Aquifer System in south Florida ...

  2. Groundwater level responses to precipitation variability in Mediterranean insular aquifers

    Science.gov (United States)

    Lorenzo-Lacruz, Jorge; Garcia, Celso; Morán-Tejeda, Enrique

    2017-09-01

    Groundwater is one of the largest and most important sources of fresh water on many regions under Mediterranean climate conditions, which are exposed to large precipitation variability that includes frequent meteorological drought episodes, and present high evapotranspiration rates and water demand during the dry season. The dependence on groundwater increases in those areas with predominant permeable lithologies, contributing to aquifer recharge and the abundance of ephemeral streams. The increasing pressure of tourism on water resources in many Mediterranean coastal areas, and uncertainty related to future precipitation and water availability, make it urgent to understand the spatio-temporal response of groundwater bodies to precipitation variability, if sustainable use of the resource is to be achieved. We present an assessment of the response of aquifers to precipitation variability based on correlations between the Standardized Precipitation Index (SPI) at various time scales and the Standardized Groundwater Index (SGI) across a Mediterranean island. We detected three main responses of aquifers to accumulated precipitation anomalies: (i) at short time scales of the SPI (24 months). The differing responses were mainly explained by differences in lithology and the percentage of highly permeable rock strata in the aquifer recharge areas. We also identified differences in the months and seasons when aquifer storages are more dependent on precipitation; these were related to climate seasonality and the degree of aquifer exploitation or underground water extraction. The recharge of some aquifers, especially in mountainous areas, is related to precipitation variability within a limited spatial extent, whereas for aquifers located in the plains, precipitation variability influence much larger areas; the topography and geological structure of the island explain these differences. Results indicate large spatial variability in the response of aquifers to precipitation in

  3. A Commune-Level Groundwater Potential Map for the Republic of Mali

    Directory of Open Access Journals (Sweden)

    Silvia Díaz-Alcaide

    2017-10-01

    Full Text Available Groundwater represents an essential resource in sub-Saharan Africa, where several hundred million people rely on aquifers for domestic supply. This paper presents a method to map groundwater potential in the Republic of Mali based on a spatially-distributed database of 26,040 boreholes. The database includes exhaustive information on key parameters such as borehole location, success rate of borehole production, depth, yield, static groundwater level or water quality. Representative variables were classified and interpreted jointly to develop a groundwater potential index for each of the 703 communes in Mali. This provides a methodological novelty because groundwater potential studies typically rely on indirect indicators such as lineaments, slope, soil moisture and landforms. Also, such large borehole databases have seldom been used to estimate groundwater potential. The highest indexes were obtained for the areas in and around the River Niger’s Inner Delta, including southern Tombouctou and the central parts of the Ségou and Mopti Regions. The lower Precambrian formations, which include the country’s thoroughly populated southern plateau, had moderate scores. The lowest groundwater potential was found in the northern part of the Kayes and Koulikoro Regions, as well as in the entire region of Kidal. By providing results at the commune scale, these outcomes show that groundwater potential across the country’s geological and hydrogeological units can be highly variable, and that local and regional-scale information may be useful for groundwater management purposes. These results are policy-relevant in a context of rapid change and population growth, where groundwater resources can be expected to be increasingly relied upon in the coming years.

  4. Stream-groundwater exchange and hydrologic turnover at the network scale

    Science.gov (United States)

    Covino, Tim; McGlynn, Brian; Mallard, John

    2011-12-01

    The exchange of water between streams and groundwater can influence stream water quality, hydrologic mass balances, and attenuate solute export from watersheds. We used conservative tracer injections (chloride, Cl-) across 10 stream reaches to investigate stream water gains and losses from and to groundwater at larger spatial and temporal scales than typically associated with hyporheic exchanges. We found strong relationships between reach discharge, median tracer velocity, and gross hydrologic loss across a range of stream morphologies and sizes in the 11.4 km2 Bull Trout Watershed of central ID. We implemented these empirical relationships in a numerical network model and simulated stream water gains and losses and subsequent fractional hydrologic turnover across the stream network. We found that stream gains and losses from and to groundwater can influence source water contributions and stream water compositions across stream networks. Quantifying proportional influences of source water contributions from runoff generation locations across the network on stream water composition can provide insight into the internal mechanisms that partially control the hydrologic and biogeochemical signatures observed along networks and at watershed outlets.

  5. Optimal Design of Multitype Groundwater Monitoring Networks Using Easily Accessible Tools.

    Science.gov (United States)

    Wöhling, Thomas; Geiges, Andreas; Nowak, Wolfgang

    2016-11-01

    Monitoring networks are expensive to establish and to maintain. In this paper, we extend an existing data-worth estimation method from the suite of PEST utilities with a global optimization method for optimal sensor placement (called optimal design) in groundwater monitoring networks. Design optimization can include multiple simultaneous sensor locations and multiple sensor types. Both location and sensor type are treated simultaneously as decision variables. Our method combines linear uncertainty quantification and a modified genetic algorithm for discrete multilocation, multitype search. The efficiency of the global optimization is enhanced by an archive of past samples and parallel computing. We demonstrate our methodology for a groundwater monitoring network at the Steinlach experimental site, south-western Germany, which has been established to monitor river-groundwater exchange processes. The target of optimization is the best possible exploration for minimum variance in predicting the mean travel time of the hyporheic exchange. Our results demonstrate that the information gain of monitoring network designs can be explored efficiently and with easily accessible tools prior to taking new field measurements or installing additional measurement points. The proposed methods proved to be efficient and can be applied for model-based optimal design of any type of monitoring network in approximately linear systems. Our key contributions are (1) the use of easy-to-implement tools for an otherwise complex task and (2) yet to consider data-worth interdependencies in simultaneous optimization of multiple sensor locations and sensor types. © 2016, National Ground Water Association.

  6. Characteristic groundwater level regimes in the capture zones of radial collector wells and importance of identification (Case study of Belgrade Groundwater Source

    Directory of Open Access Journals (Sweden)

    Božović Đorđije

    2016-01-01

    Full Text Available Assessment of the operating modes of radial collector wells reveals that the pumping levels in the well caissons are very low relative to the depth/elevation of the laterals, which is a common occurrence at Belgrade Groundwater Source. As a result, well discharge capacities vary over a broad range and groundwater levels in the capture zones differ even when the rate of discharge is the same. Five characteristic groundwater level regimes are identified and their origin is analyzed using representative wells as examples. The scope and type of background information needed to identify the groundwater level regime are presented and an interpretation approach is proposed for preliminary assessment of the aquifer potential at the well site for providing the needed amount of groundwater. [Projekat Ministarstva nauke Republike Srbije, br. OI176022, br. TR33039 i br. III43004

  7. Arsenic levels in the groundwater of Korea and the urinary excretion among contaminated area.

    Science.gov (United States)

    Park, Jung-Duck; Choi, Seong-Jin; Choi, Byung-Sun; Lee, Choong-Ryeol; Kim, Heon; Kim, Yong-Dae; Park, Kyung-Soo; Lee, Young-Jo; Kang, Seojin; Lim, Kyung-Min; Chung, Jin-Ho

    2016-09-01

    Drinking water is a main source of human exposure to arsenic. Hence, the determination of arsenic in groundwater is essential to assess its impact on public health. Here, we report arsenic levels in the groundwater of 722 sites covering all six major provinces of Korea. Water was sampled in two occasions (summer, 722 sites and winter, 636 sites) and the arsenic levels were measured with highly sensitive inductively coupled plasma-mass spectrometry method (limit of detection, 0.1 μg/l) to encompass the current drinking water standard (arsenic in groundwater ranged from 0.1 to 48.4 μg/l. A 88.0-89.0% of sites were 10 μg/l. Notably, urinary arsenic excretion of people around these regions was markedly higher compared with non-contaminated areas (arsenic-contaminated groundwater may contribute to its systemic exposure.

  8. Process-based modelling to evaluate simulated groundwater levels and frequencies in a Chalk catchment in south-western England

    Science.gov (United States)

    Brenner, Simon; Coxon, Gemma; Howden, Nicholas J. K.; Freer, Jim; Hartmann, Andreas

    2018-02-01

    Chalk aquifers are an important source of drinking water in the UK. Due to their properties, they are particularly vulnerable to groundwater-related hazards like floods and droughts. Understanding and predicting groundwater levels is therefore important for effective and safe water management. Chalk is known for its high porosity and, due to its dissolvability, exposed to karstification and strong subsurface heterogeneity. To cope with the karstic heterogeneity and limited data availability, specialised modelling approaches are required that balance model complexity and data availability. In this study, we present a novel approach to evaluate simulated groundwater level frequencies derived from a semi-distributed karst model that represents subsurface heterogeneity by distribution functions. Simulated groundwater storages are transferred into groundwater levels using evidence from different observations wells. Using a percentile approach we can assess the number of days exceeding or falling below selected groundwater level percentiles. Firstly, we evaluate the performance of the model when simulating groundwater level time series using a spilt sample test and parameter identifiability analysis. Secondly, we apply a split sample test to the simulated groundwater level percentiles to explore the performance in predicting groundwater level exceedances. We show that the model provides robust simulations of discharge and groundwater levels at three observation wells at a test site in a chalk-dominated catchment in south-western England. The second split sample test also indicates that the percentile approach is able to reliably predict groundwater level exceedances across all considered timescales up to their 75th percentile. However, when looking at the 90th percentile, it only provides acceptable predictions for long time periods and it fails when the 95th percentile of groundwater exceedance levels is considered. By modifying the historic forcings of our model

  9. Fe and Mn levels regulated by agricultural activities in alluvial groundwaters underneath a flooded paddy field

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kangjoo [School of Civil and Environmental Engineering, Kunsan National University, Jeonbuk 573-701 (Korea, Republic of)], E-mail: kangjoo@kunsan.ac.kr; Kim, Hyun-Jung; Choi, Byoung-Young; Kim, Seok-Hwi; Park, Ki-hoon [School of Civil and Environmental Engineering, Kunsan National University, Jeonbuk 573-701 (Korea, Republic of); Park, Eungyu [Department of Geology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Koh, Dong-Chan [Korea Institute of Geoscience and Mineral Resources, Daejeon 305-350 (Korea, Republic of); Yun, Seong-Taek [Department of Earth and Environmental Sciences, Korea University, Seoul 136-701 (Korea, Republic of)

    2008-01-15

    Iron and Mn concentrations in fresh groundwaters of alluvial aquifers are generally high in reducing conditions reflecting low SO{sub 4} concentrations. The mass balance and isotopic approaches of this study demonstrate that reduction of SO{sub 4}, supplied from agricultural activities such as fertilization and irrigation, is important in lowering Fe and Mn levels in alluvial groundwaters underneath a paddy field. This study was performed to investigate the processes regulating Fe and Mn levels in groundwaters of a point bar area, which has been intensively used for flood cultivation. Four multilevel-groundwater samplers were installed to examine the relationship between geology and the vertical changes in water chemistry. The results show that Fe and Mn levels are regulated by the presence of NO{sub 3} at shallow depths and by SO{sub 4} reduction at the greater depths. Isotopic and mass balance analyses revealed that NO{sub 3} and SO{sub 4} in groundwater are mostly supplied from the paddy field, suggesting that the Fe-and Mn-rich zone of the study area is confined by the agricultural activities. For this reason, the geologic conditions controlling the infiltration of agrochemicals are also important for the occurrence of Fe/Mn-rich groundwaters in the paddy field area.

  10. Fe and Mn levels regulated by agricultural activities in alluvial groundwaters underneath a flooded paddy field

    International Nuclear Information System (INIS)

    Kim, Kangjoo; Kim, Hyun-Jung; Choi, Byoung-Young; Kim, Seok-Hwi; Park, Ki-hoon; Park, Eungyu; Koh, Dong-Chan; Yun, Seong-Taek

    2008-01-01

    Iron and Mn concentrations in fresh groundwaters of alluvial aquifers are generally high in reducing conditions reflecting low SO 4 concentrations. The mass balance and isotopic approaches of this study demonstrate that reduction of SO 4 , supplied from agricultural activities such as fertilization and irrigation, is important in lowering Fe and Mn levels in alluvial groundwaters underneath a paddy field. This study was performed to investigate the processes regulating Fe and Mn levels in groundwaters of a point bar area, which has been intensively used for flood cultivation. Four multilevel-groundwater samplers were installed to examine the relationship between geology and the vertical changes in water chemistry. The results show that Fe and Mn levels are regulated by the presence of NO 3 at shallow depths and by SO 4 reduction at the greater depths. Isotopic and mass balance analyses revealed that NO 3 and SO 4 in groundwater are mostly supplied from the paddy field, suggesting that the Fe-and Mn-rich zone of the study area is confined by the agricultural activities. For this reason, the geologic conditions controlling the infiltration of agrochemicals are also important for the occurrence of Fe/Mn-rich groundwaters in the paddy field area

  11. Decomposition of groundwater level fluctuations using transfer modelling in an area with shallow to deep unsaturated zones

    Science.gov (United States)

    Gehrels, J. C.; van Geer, F. C.; de Vries, J. J.

    1994-05-01

    Time series analysis of the fluctuations in shallow groundwater levels in the Netherlands lowlands have revealed a large-scale decline in head during recent decades as a result of an increase in land drainage and groundwater withdrawal. The situation is more ambiguous in large groundwater bodies located in the eastern part of the country, where the unsaturated zone increases from near zero along the edges to about 40 m in the centre of the area. As depth of the unsaturated zone increases, groundwater level reacts with an increasing delay to fluctuations in climate and influences of human activities. The aim of the present paper is to model groundwater level fluctuations in these areas using a linear stochastic transfer function model, relating groundwater levels to estimated precipitation excess, and to separate artificial components from the natural groundwater regime. In this way, the impact of groundwater withdrawal and the reclamation of a 1000 km 2 polder area on the groundwater levels in the adjoining higher ground could be assessed. It became evident that the linearity assumption of the transfer functions becomes a serious drawback in areas with the deepest groundwater levels, because of non-linear processes in the deep unsaturated zone and the non-synchronous arrival of recharge in the saturated zone. Comparison of the results from modelling the influence of reclamation with an analytical solution showed that the lowering of groundwater level is partly compensated by reduced discharge and therefore is less than expected.

  12. Preliminary investigation of the effects of sea-level rise on groundwater levels in New Haven, Connecticut

    Science.gov (United States)

    Bjerklie, David M.; Mullaney, John R.; Stone, Janet R.; Skinner, Brian J.; Ramlow, Matthew A.

    2012-01-01

    Global sea level rose about 0.56 feet (ft) (170 millimeters (mm)) during the 20th century. Since the 1960s, sea level has risen at Bridgeport, Connecticut, about 0.38 ft (115 mm), at a rate of 0.008 ft (2.56 mm + or - 0.58 mm) per year. With regional subsidence, and with predicted global climate change, sea level is expected to continue to rise along the northeast coast of the United States through the 21st century. Increasing sea levels will cause groundwater levels in coastal areas to rise in order to adjust to the new conditions. Some regional climate models predict wetter climate in the northeastern United States under some scenarios. Scenarios for the resulting higher groundwater levels have the potential to inundate underground infrastructure in lowlying coastal cities. New Haven is a coastal city in Connecticut surrounded and bisected by tidally affected waters. Monitoring of water levels in wells in New Haven from August 2009 to July 2010 indicates the complex effects of urban influence on groundwater levels. The response of groundwater levels to recharge and season varied considerably from well to well. Groundwater temperatures varied seasonally, but were warmer than what was typical for Connecticut, and they seem to reflect the influence of the urban setting, including the effects of conduits for underground utilities. Specific conductance was elevated in many of the wells, indicating the influence of urban activities or seawater in Long Island Sound. A preliminary steady-state model of groundwater flow for part of New Haven was constructed using MODFLOW to simulate current groundwater levels (2009-2010) and future groundwater levels based on scenarios with a rise of 3 ft (0.91 meters (m)) in sea level, which is predicted for the end of the 21st century. An additional simulation was run assuming a 3-ft rise in sea level combined with a 12-percent increase in groundwater recharge. The model was constructed from existing hydrogeologic information for the

  13. Groundwater level prediction of landslide based on classification and regression tree

    Directory of Open Access Journals (Sweden)

    Yannan Zhao

    2016-09-01

    Full Text Available According to groundwater level monitoring data of Shuping landslide in the Three Gorges Reservoir area, based on the response relationship between influential factors such as rainfall and reservoir level and the change of groundwater level, the influential factors of groundwater level were selected. Then the classification and regression tree (CART model was constructed by the subset and used to predict the groundwater level. Through the verification, the predictive results of the test sample were consistent with the actually measured values, and the mean absolute error and relative error is 0.28 m and 1.15% respectively. To compare the support vector machine (SVM model constructed using the same set of factors, the mean absolute error and relative error of predicted results is 1.53 m and 6.11% respectively. It is indicated that CART model has not only better fitting and generalization ability, but also strong advantages in the analysis of landslide groundwater dynamic characteristics and the screening of important variables. It is an effective method for prediction of ground water level in landslides.

  14. Effect of coupling behavior on groundwater flow for geological disposal of radioactive high level waste

    International Nuclear Information System (INIS)

    Kurikami, Hiroshi; Kobayashi, Akira; Ohnishi, Yuzo; Chijimatsu, Masakazu

    2003-01-01

    In order to estimate the effects of coupled thermal-hydraulic-mechanical phenomena in near-field for geological disposal of high-level radioactive waste on a vast groundwater flow system, a far-field analysis was simulated based on the results of the simulation of coupled phenomena in near-field using averaged tensor and heat flux. From the results of the coupled analyses of near-field and far-field it was clarified that groundwater flow system was influenced by coupled phenomena in near-field. Moreover, it can be said that groundwater flux into a disposal tunnel is regarded as a complement to safety assessment of a disposal because it strongly correlates with traveling time of groundwater. (author)

  15. Russian State Leveling Network (present and future)

    Science.gov (United States)

    Mazurova, Elena; Kopeikin, Sergei; Karpik, Aleksander

    2017-04-01

    In August 2016 the sixth session of the United Nations Committee of Experts of Global Geospatial Information Management (UN-GGIM) endorsed the roadmap for the development of a Global Geodetic Reference Frame (GGRF) and urged countries to join efforts for its creation. In response to the UN appeal in this article describes the current state of the high-precision Leveling Network in Russia and prospects of its development. In this paper, we consider projects related to the construction of new high-precision leveling lines by the classical methods, as well as issues of creating high-precision leveling network, associated with the development and implementation of a fundamentally new method of determining heights in geodesy - chronometric leveling based on the application of quantum metrology of time and the fundamental laws of general relativity. Keywords: leveling network, chronometric leveling, quantum metrology of time, the general theory of relativity.

  16. Constructing level-2 phylogenetic networks from triplets

    OpenAIRE

    Iersel, Leo; Keijsper, J.C.M.; Kelk, Steven; Stougie, Leen; Hagen, F.; Boekhout, T.; Vingron, M.; Wong, L.

    2009-01-01

    htmlabstractJansson and Sung showed that, given a dense set of input triplets T (representing hypotheses about the local evolutionary relationships of triplets of taxa), it is possible to determine in polynomial time whether there exists a level-1 network consistent with T, and if so to construct such a network (Inferring a Level-1 Phylogenetic Network from a Dense Set of Rooted Triplets, Theoretical Computer Science, 363, pp. 60-68 (2006)). Here we extend this work by showing that this probl...

  17. The Importance of Institutional Design for Distributed Local-Level Governance of Groundwater: The Case of California’s Sustainable Groundwater Management Act

    Directory of Open Access Journals (Sweden)

    Michael Kiparsky

    2017-09-01

    Full Text Available In many areas of the world, groundwater resources are increasingly stressed, and unsustainable use has become common. Where existing mechanisms for governing groundwater are ineffective or nonexistent, new ones need to be developed. Local level groundwater governance provides an intriguing alternative to top-down models, with the promise of enabling management to better match the diversity of physical and social conditions in groundwater basins. One such example is emerging in California, USA, where new state law requires new local agencies to self-organize and act to achieve sustainable groundwater management. In this article, we draw on insights from research on common pool resource management and natural resources governance to develop guidelines for institutional design for local groundwater governance, grounded in California’s developing experience. We offer nine criteria that can be used as principles or standards in the evaluation of institutional design for local level groundwater governance: scale, human capacity, funding, authority, independence, representation, participation, accountability, and transparency. We assert that local governance holds promise as an alternative to centralized governance in some settings but that its success will depend heavily on the details of its implementation. Further, for local implementation to achieve its promise, there remain important complementary roles for centralized governance. California’s developing experience with local level groundwater management in dozens of basins across the state provides a unique opportunity to test and assess the importance and influence of these criteria.

  18. Indicative effects of climate change on groundwater levels in Estonian raised bogs over 50 years

    Directory of Open Access Journals (Sweden)

    E. Lode

    2017-08-01

    Full Text Available Analyses of 50-year (1962–2011 monthly air temperature and precipitation data indicated substantial climate change in the locations of two raised bogs (Linnusaare and Männikjärve in central-east Estonia. During recent years the cross-year winter air temperature increased by 1.7 ºC, while the cold-season precipitation increased by 4 mm. The fluctuation amplitude of temperature and precipitation values decreased. Snow depth proved to be the most sensitive variable to winter warming, followed by groundwater levels together with mean and maximum soil frosts. Long-term groundwater levels on the domes of the bogs and in the forested/treed lagg areas were 0.3−0.4 m and 0.4−0.8 m below the soil surface, respectively. Warming caused changes in groundwater level amplitude of 3−22 cm in the bog domes and 3−14 cm in the forested lagg zones. The lowest groundwater levels in ridge-pool ecotopes at Männikjärve rose by 6−10 cm (i.e. these ecotopes became wetter; but the incidence of low groundwater levels increased in most ecotopes, indicating a more general trend towards drier conditions in the bog.

  19. Sensitivity analysis of hydrogeological parameters affecting groundwater storage change caused by sea level rise

    Science.gov (United States)

    Shin, J.; Kim, K.-H.; Lee, K.-K.

    2012-04-01

    Sea level rise, which is one of the representative phenomena of climate changes caused by global warming, can affect groundwater system. The rising trend of the sea level caused by the global warming is reported to be about 3 mm/year for the most recent 10 year average (IPCC, 2007). The rate of sea level rise around the Korean peninsula is reported to be 2.30±2.22 mm/yr during the 1960-1999 period (Cho, 2002) and 2.16±1.77 mm/yr (Kim et al., 2009) during the 1968-2007 period. Both of these rates are faster than the 1.8±0.5 mm/yr global average for the similar 1961-2003 period (IPCC, 2007). In this study, we analyzed changes in the groundwater environment affected by the sea level rise by using an analytical methodology. We tried to find the most effective parameters of groundwater amount change in order to estimate the change in fresh water amount in coastal groundwater. A hypothetical island model of a cylindrical shape in considered. The groundwater storage change is bi-directional as the sea level rises according to the natural and hydrogeological conditions. Analysis of the computation results shows that topographic slope and hydraulic conductivity are the most sensitive factors. The contributions of the groundwater recharge rate and the thickness of aquifer below sea level are relatively less effective. In the island with steep seashore slopes larger than 1~2 degrees or so, the storage amount of fresh water in a coastal area increases as sea level rises. On the other hand, when sea level drops, the storage amount decreases. This is because the groundwater level also rises with the rising sea level in steep seashores. For relatively flat seashores, where the slope is smaller than around 1-2 degrees, the storage amount of coastal fresh water decreases when the sea level rises because the area flooded by the rising sea water is increased. The volume of aquifer fresh water in this circumstance is greatly reduced in proportion to the flooded area with the sea

  20. 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

  1. Enhanced Multi-Objective Optimization of Groundwater Monitoring Networks

    DEFF Research Database (Denmark)

    Bode, Felix; Binning, Philip John; Nowak, Wolfgang

    Drinking-water well catchments include many sources for potential contaminations like gas stations or agriculture. Finding optimal positions of monitoring wells for such purposes is challenging because there are various parameters (and their uncertainties) that influence the reliability...... and optimality of any suggested monitoring location or monitoring network. The goal of this project is to develop and establish a concept to assess, design, and optimize early-warning systems within well catchments. Such optimal monitoring networks need to optimize three competing objectives: (1) a high...... be reduced to a minimum. The method is based on numerical simulation of flow and transport in heterogeneous porous media coupled with geostatistics and Monte-Carlo, wrapped up within the framework of formal multi-objective optimization. In order to gain insight into the flow and transport physics...

  2. Extent, perception and mitigation of damage due to high groundwater levels in the city of Dresden, Germany

    Directory of Open Access Journals (Sweden)

    H. Kreibich

    2009-07-01

    Full Text Available Flood risk analysis and management plans mostly neglect groundwater flooding, i.e. high groundwater levels. However, rising groundwater may cause considerable damage to buildings and infrastructure. To improve the knowledge about groundwater flooding and support risk management, a survey was undertaken in the city of Dresden (Saxony, Germany, resulting in 605 completed interviews with private households endangered by high groundwater levels. The reported relatively low flood impact and damage of groundwater floods in comparison with mixed floods was reflected by its scarce perception: Hardly anybody thinks about the risk of groundwater flooding. The interviewees thought that public authorities and not themselves, should be mainly responsible for preparedness and emergency response. Up to now, people do not include groundwater risk in their decision processes on self protection. The implementation of precautionary measures does not differ between households with groundwater or with mixed flood experience. However, less households undertake emergency measures when expecting a groundwater flood only. The state of preparedness should be further improved via an intensified risk communication about groundwater flooding by the authorities. Conditions to reach the endangered population are good, since 70% of the interviewed people are willing to inform themselves about groundwater floods. Recommendations for an improved risk communication are given.

  3. Multi-Level Secure Local Area Network

    OpenAIRE

    Naval Postgraduate School (U.S.); Center for Information Systems Studies Security and Research (CISR)

    2011-01-01

    Multi-Level Secure Local Area Network is a cost effective, multi-level, easy to use office environment leveraging existing high assurance technology. The Department of Defense and U.S. Government have an identified need to securely share information classified at differing security levels. Because there exist no commercial solutions to this problem, NPS is developing a MLS LAN. The MLS LAN extends high assurance capabilities of an evaluated multi-level secure system to commercial personal com...

  4. Tracking artificial sweeteners and pharmaceuticals introduced into urban groundwater by leaking sewer networks.

    Science.gov (United States)

    Wolf, Leif; Zwiener, Christian; Zemann, Moritz

    2012-07-15

    There is little quantitative information on the temporal trends of pharmaceuticals and other emerging compounds, including artificial sweeteners, in urban groundwater and their suitability as tracers to inform urban water management. In this study, pharmaceuticals and artificial sweeteners were monitored over 6 years in a shallow urban groundwater body along with a range of conventional sewage tracers in a network of observation wells that were specifically constructed to assess sewer leakage. Out of the 71 substances screened, 24 were detected at above the analytical detection limit. The most frequent compounds were the iodinated X-ray contrast medium amidotrizoic acid (35.3%), the anticonvulsant carbamazepine (33.3%) and the artificial sweetener acesulfame (27.5%), while all other substances occurred in less than 10% of the screened wells. The results from the group of specifically constructed focus wells within 10 m of defective sewers confirmed sewer leaks as being a major entrance pathway into the groundwater. The spatial distribution of pharmaceuticals and artificial sweeteners corresponds well with predictions by pipeline leakage models, which operate on optical sewer condition monitoring data and hydraulic information. Correlations between the concentrations of carbamazepine, iodinated X-ray contrast media and artificial sweeteners were weak to non-existent. Peak concentrations of up to 4130 ng/l of amidotrizoic acid were found in the groundwater downstream of the local hospital. The analysis of 168 samples for amidotrizoic acid, taken at 5 different occasions, did not show significant temporal trends for the years 2002-2008, despite changed recommendations in the medical usage of amidotrizoic acid. The detailed results show that the current mass balance approaches for urban groundwater bodies must be adapted to reflect the spatially distributed leaks and the variable wastewater composition in addition to the lateral and horizontal groundwater fluxes. Crown

  5. Network Communication for Low Level RF Control

    International Nuclear Information System (INIS)

    Liu Weiqing; Yin Chengke; Zhang Tongxuan; Fu Zechuan; Liu Jianfei

    2009-01-01

    Low Level RF (LLRF) control system for storage ring of Shanghai Synchrotron Radiation Facility (SSRF) has been built by digital technology. The settings of parameters and the feedback loop status are carried out through the network communication interface, and the local oscillation and clock, which is the important component of the digital LLRF control system, are also configured through network communication. NIOS II processor was employed as a core to build the embedded system with a real-time operating system MicroC/OS-II, finally Lightweight TCP/IP (LwIP) was used to achieve the communication interface. The communication network is stable after a long-term operation. (authors)

  6. A method of groundwater quality assessment based on fuzzy network-CANFIS and geographic information system (GIS)

    Science.gov (United States)

    Gholami, V.; Khaleghi, M. R.; Sebghati, M.

    2017-11-01

    The process of water quality testing is money/time-consuming, quite important and difficult stage for routine measurements. Therefore, use of models has become commonplace in simulating water quality. In this study, the coactive neuro-fuzzy inference system (CANFIS) was used to simulate groundwater quality. Further, geographic information system (GIS) was used as the pre-processor and post-processor tool to demonstrate spatial variation of groundwater quality. All important factors were quantified and groundwater quality index (GWQI) was developed. The proposed model was trained and validated by taking a case study of Mazandaran Plain located in northern part of Iran. The factors affecting groundwater quality were the input variables for the simulation, whereas GWQI index was the output. The developed model was validated to simulate groundwater quality. Network validation was performed via comparison between the estimated and actual GWQI values. In GIS, the study area was separated to raster format in the pixel dimensions of 1 km and also by incorporation of input data layers of the Fuzzy Network-CANFIS model; the geo-referenced layers of the effective factors in groundwater quality were earned. Therefore, numeric values of each pixel with geographical coordinates were entered to the Fuzzy Network-CANFIS model and thus simulation of groundwater quality was accessed in the study area. Finally, the simulated GWQI indices using the Fuzzy Network-CANFIS model were entered into GIS, and hence groundwater quality map (raster layer) based on the results of the network simulation was earned. The study's results confirm the high efficiency of incorporation of neuro-fuzzy techniques and GIS. It is also worth noting that the general quality of the groundwater in the most studied plain is fairly low.

  7. Regional specific groundwater arsenic levels and neuropsychological functioning: a cross-sectional study.

    Science.gov (United States)

    Edwards, Melissa; Johnson, Leigh; Mauer, Cortney; Barber, Robert; Hall, James; O'Bryant, Sid

    2014-01-01

    The purpose of the study was to examine the link between geographic information system (GIS)-estimated regional specific groundwater levels and neuropsychological functioning in a sample of individuals with and without cognitive impairment. This cross-sectional study design analyzed data from 1390 participants (733 Alzheimer's disease, 127 Mild Cognitive Impairment, and 530 with normal cognition) enrolled in the Texas Alzheimer's Research and Care Consortium. GISs analyses were used to estimate regional specific groundwater arsenic concentrations using the Environmental Systems Research Institute and arsenic concentrations from the Texas Water Development Board. In the full cohort, regional specific arsenic concentrations were positively associated with language abilities (p = 0.008), but associated with poorer verbal memory, immediate (p = 0.008), and delayed (p arsenic being related with cognition most prominently among mild cognitive impairment cases. Overall, estimated regional specific groundwater arsenic levels were negatively associated with neuropsychological performance.

  8. Effects of sea-level rise on barrier island groundwater system dynamics: ecohydrological implications

    Science.gov (United States)

    Masterson, John P.; Fienen, Michael N.; Thieler, E. Robert; Gesch, Dean B.; Gutierrez, Benjamin T.; Plant, Nathaniel G.

    2014-01-01

    We used a numerical model to investigate how a barrier island groundwater system responds to increases of up to 60 cm in sea level. We found that a sea-level rise of 20 cm leads to substantial changes in the depth of the water table and the extent and depth of saltwater intrusion, which are key determinants in the establishment, distribution and succession of vegetation assemblages and habitat suitability in barrier islands ecosystems. In our simulations, increases in water-table height in areas with a shallow depth to water (or thin vadose zone) resulted in extensive groundwater inundation of land surface and a thinning of the underlying freshwater lens. We demonstrated the interdependence of the groundwater response to island morphology by evaluating changes at three sites. This interdependence can have a profound effect on ecosystem composition in these fragile coastal landscapes under long-term changing climatic conditions.

  9. Achieving Network Level Privacy in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sungyoung Lee

    2010-02-01

    Full Text Available Full network level privacy has often been categorized into four sub-categories: Identity, Route, Location and Data privacy. Achieving full network level privacy is a critical and challenging problem due to the constraints imposed by the sensor nodes (e.g., energy, memory and computation power, sensor networks (e.g., mobility and topology and QoS issues (e.g., packet reach-ability and timeliness. In this paper, we proposed two new identity, route and location privacy algorithms and data privacy mechanism that addresses this problem. The proposed solutions provide additional trustworthiness and reliability at modest cost of memory and energy. Also, we proved that our proposed solutions provide protection against various privacy disclosure attacks, such as eavesdropping and hop-by-hop trace back attacks.

  10. Analysis of 1997–2008 groundwater level changes in the upper Deschutes Basin, Central Oregon

    Science.gov (United States)

    Gannett, Marshall W.; Lite, Kenneth E.

    2013-01-01

    Groundwater-level monitoring in the upper Deschutes Basin of central Oregon from 1997 to 2008 shows water-level declines in some places that are larger than might be expected from climate variations alone, raising questions regarding the influence of groundwater pumping, canal lining (which decreases recharge), and other human influences. Between the mid-1990s and mid-2000s, water levels in the central part of the basin near Redmond steadily declined as much as 14 feet. Water levels in the Cascade Range, in contrast, rose more than 20 feet from the mid-1990s to about 2000, and then declined into the mid-2000s, with little or no net change. An existing U.S. Geological Survey regional groundwater-flow model was used to gain insights into groundwater-level changes from 1997 to 2008, and to determine the relative influence of climate, groundwater pumping, and irrigation canal lining on observed water-level trends. To utilize the model, input datasets had to be extended to include post-1997 changes in groundwater pumping, changes in recharge from precipitation, irrigation canal leakage, and deep percolation of applied irrigation water (also known as on-farm loss). Mean annual groundwater recharge from precipitation during the 1999–2008 period was 25 percent less than during the 1979–88 period because of drying climate conditions. This decrease in groundwater recharge is consistent with measured decreases in streamflow and discharge to springs. For example, the mean annual discharge of Fall River, which is a spring-fed stream, decreased 12 percent between the 1979–88 and 1999–2008 periods. Between the mid-1990s and late 2000s, groundwater pumping for public-supply and irrigation uses increased from about 32,500 to 52,000 acre-feet per year, partially because of population growth. Between 1997 and 2008, the rate of recharge from leaking irrigation canals decreased by about 58,000 acre-feet per year as a result of lining and piping of canals. Decreases in recharge

  11. Hydrographs Showing Ground-Water Level Changes for Selected Wells in the Lower Skagit River Basin, Washington

    Science.gov (United States)

    Fasser, E.T.; Julich, R.J.

    2009-01-01

    Hydrographs for selected wells in the Lower Skagit River basin, Washington, are presented in an interactive web-based map to illustrate monthly and seasonal changes in ground-water levels in the study area. Ground-water level data and well information were collected by the U.S. Geological Survey using standard techniques and were stored in the USGS National Water Information System (NWIS), Ground-Water Site-Inventory (GWSI) System.

  12. Hydrographs showing groundwater levels for selected wells in the Puyallup River watershed and vicinity, Pierce and King Counties, Washington

    Science.gov (United States)

    Lane, R.C.; Julich, R.J.; Justin, G.B.

    2013-01-01

    Hydrographs of groundwater levels for selected wells in and adjacent to the Puyallup River watershed in Pierce and King Counties, Washington, are presented using an interactive Web-based map of the study area to illustrate changes in groundwater levels on a monthly and seasonal basis. The interactive map displays well locations that link to the hydrographs, which in turn link to the U.S. Geological Survey National Water Information System, Groundwater Site Inventory System.

  13. Groundwater reorganization in the Floridan aquifer following Holocene sea-level rise

    Science.gov (United States)

    Morrissey, Sheila K.; Clark, Jordan F.; Bennett, Michael; Richardson, Emily; Stute, Martin

    2010-10-01

    Sea-level fluctuations, particularly those associated with glacial-interglacial cycles, can have profound impacts on the flow and circulation of coastal groundwater: the water found at present in many coastal aquifers may have been recharged during the last glacial period, when sea level was over 100m lower than present, and thus is not in equilibrium with present recharge conditions. Here we show that the geochemistry of the groundwater found in the Floridan Aquifer System in south Florida is best explained by a reorganization of groundwater flow following the sea-level rise at the end of the Last Glacial Maximum approximately 18,000 years ago. We find that the geochemistry of the fresh water found in the upper aquifers at present is consistent with recharge from meteoric water during the last glacial period. The lower aquifer, however, consists of post-sea-level-rise salt water that is most similar to that of the Straits of Florida, though with some dilution from the residual fresh water from the last glacial period circulation. We therefore suggest that during the last glacial period, the entire Floridan Aquifer System was recharged with meteoric waters. After sea level rose, the increased hydraulic head reduced the velocity of the groundwater flow. This velocity reduction trapped the fresh water in the upper aquifers and initiated saltwater circulation in the lower aquifer.

  14. Hydrographs Showing Groundwater Level Changes for Selected Wells in the Chambers-Clover Creek Watershed and Vicinity, Pierce County, Washington

    Science.gov (United States)

    Justin, G.B.; Julich, R.; Payne, K.L.

    2009-01-01

    Selected groundwater level hydrographs for the Chambers-Clover Creek watershed (CCCW) and vicinity, Washington, are presented in an interactive web-based map to illustrate changes in groundwater levels in and near the CCCW on a monthly and seasonal basis. Hydrographs are linked to points corresponding to the well location on an interactive map of the study area. Groundwater level data and well information from Federal, State, and local agencies were obtained from the U.S. Geological Survey National Water Information System (NWIS), Groundwater Site Inventory (GWSI) System.

  15. Numerical study of groundwater flow cycling controlled by seawater/freshwater interaction in a coastal karst aquifer through conduit network using CFPv2

    Science.gov (United States)

    Xu, Zexuan; Hu, Bill X.; Davis, Hal; Kish, Stephen

    2015-11-01

    In this study, a groundwater flow cycling in a karst springshed and an interaction between two springs, Spring Creek Springs and Wakulla Springs, through a subground conduit network are numerically simulated using CFPv2, the latest research version of MODFLOW-CFP (Conduit Flow Process). The Spring Creek Springs and Wakulla Springs, located in a marine estuary and 11 miles inland, respectively, are two major groundwater discharge spots in the Woodville Karst Plain (WKP), North Florida, USA. A three-phase conceptual model of groundwater flow cycling between the two springs and surface water recharge from a major surface creek (Lost Creek) was proposed in various rainfall conditions. A high permeable subground karst conduit network connecting the two springs was found by tracer tests and cave diving. Flow rate of discharge, salinity, sea level and tide height at Spring Creek Springs could significantly affect groundwater discharge and water stage at Wakulla Springs simultaneously. Based on the conceptual model, a numerical hybrid discrete-continuum groundwater flow model is developed using CFPv2 and calibrated by field measurements. Non-laminar flows in conduits and flow exchange between conduits and porous medium are implemented in the hybrid coupling numerical model. Time-variable salinity and equivalent freshwater head boundary conditions at the submarine spring as well as changing recharges have significant impacts on seawater/freshwater interaction and springs' discharges. The developed numerical model is used to simulate the dynamic hydrological process and quantitatively represent the three-phase conceptual model from June 2007 to June 2010. Simulated results of two springs' discharges match reasonably well to measurements with correlation coefficients 0.891 and 0.866 at Spring Creeks Springs and Wakulla Springs, respectively. The impacts of sea level rise on regional groundwater flow field and relationship between the inland springs and submarine springs are

  16. Numerical study of groundwater flow cycling controlled by seawater/freshwater interaction in a coastal karst aquifer through conduit network using CFPv2.

    Science.gov (United States)

    Xu, Zexuan; Hu, Bill X; Davis, Hal; Kish, Stephen

    2015-11-01

    In this study, a groundwater flow cycling in a karst springshed and an interaction between two springs, Spring Creek Springs and Wakulla Springs, through a subground conduit network are numerically simulated using CFPv2, the latest research version of MODFLOW-CFP (Conduit Flow Process). The Spring Creek Springs and Wakulla Springs, located in a marine estuary and 11 miles inland, respectively, are two major groundwater discharge spots in the Woodville Karst Plain (WKP), North Florida, USA. A three-phase conceptual model of groundwater flow cycling between the two springs and surface water recharge from a major surface creek (Lost Creek) was proposed in various rainfall conditions. A high permeable subground karst conduit network connecting the two springs was found by tracer tests and cave diving. Flow rate of discharge, salinity, sea level and tide height at Spring Creek Springs could significantly affect groundwater discharge and water stage at Wakulla Springs simultaneously. Based on the conceptual model, a numerical hybrid discrete-continuum groundwater flow model is developed using CFPv2 and calibrated by field measurements. Non-laminar flows in conduits and flow exchange between conduits and porous medium are implemented in the hybrid coupling numerical model. Time-variable salinity and equivalent freshwater head boundary conditions at the submarine spring as well as changing recharges have significant impacts on seawater/freshwater interaction and springs' discharges. The developed numerical model is used to simulate the dynamic hydrological process and quantitatively represent the three-phase conceptual model from June 2007 to June 2010. Simulated results of two springs' discharges match reasonably well to measurements with correlation coefficients 0.891 and 0.866 at Spring Creeks Springs and Wakulla Springs, respectively. The impacts of sea level rise on regional groundwater flow field and relationship between the inland springs and submarine springs are

  17. Groundwater-level trends and forecasts, and salinity trends, in the Azraq, Dead Sea, Hammad, Jordan Side Valleys, Yarmouk, and Zarqa groundwater basins, Jordan

    Science.gov (United States)

    Goode, Daniel J.; Senior, Lisa A.; Subah, Ali; Jaber, Ayman

    2013-01-01

    Changes in groundwater levels and salinity in six groundwater basins in Jordan were characterized by using linear trends fit to well-monitoring data collected from 1960 to early 2011. On the basis of data for 117 wells, groundwater levels in the six basins were declining, on average about -1 meter per year (m/yr), in 2010. The highest average rate of decline, -1.9 m/yr, occurred in the Jordan Side Valleys basin, and on average no decline occurred in the Hammad basin. The highest rate of decline for an individual well was -9 m/yr. Aquifer saturated thickness, a measure of water storage, was forecast for year 2030 by using linear extrapolation of the groundwater-level trend in 2010. From 30 to 40 percent of the saturated thickness, on average, was forecast to be depleted by 2030. Five percent of the wells evaluated were forecast to have zero saturated thickness by 2030. Electrical conductivity was used as a surrogate for salinity (total dissolved solids). Salinity trends in groundwater were much more variable and less linear than groundwater-level trends. The long-term linear salinity trend at most of the 205 wells evaluated was not increasing, although salinity trends are increasing in some areas. The salinity in about 58 percent of the wells in the Amman-Zarqa basin was substantially increasing, and the salinity in Hammad basin showed a long-term increasing trend. Salinity increases were not always observed in areas with groundwater-level declines. The highest rates of salinity increase were observed in regional discharge areas near groundwater pumping centers.

  18. Impacts of hydrogeological characteristics on groundwater-level changes induced by earthquakes

    Science.gov (United States)

    Liu, Ching-Yi; Chia, Yeeping; Chuang, Po-Yu; Chiu, Yung-Chia; Tseng, Tai-Lin

    2018-03-01

    Changes in groundwater level during earthquakes have been reported worldwide. In this study, field observations of co-seismic groundwater-level changes in wells under different aquifer conditions and sampling intervals due to near-field earthquake events in Taiwan are presented. Sustained changes, usually observed immediately after earthquakes, are found in the confined aquifer. Oscillatory changes due to the dynamic strain triggered by passing earthquake waves can only be recorded by a high-frequency data logger. While co-seismic changes recover rapidly in an unconfined aquifer, they can sustain for months or longer in a confined aquifer. Three monitoring wells with long-term groundwater-level data were examined to understand the association of co-seismic changes with local hydrogeological conditions. The finite element software ABAQUS is used to simulate the pore-pressure changes induced by the displacements due to fault rupture. The calculated co-seismic change in pore pressure is related to the compressibility of the formation. The recovery rate of the change is rapid in the unconfined aquifer due to the hydrostatic condition at the water table, but slow in the confined aquifer due to the less permeable confining layer. Fracturing of the confining layer during earthquakes may enhance the dissipation of pore pressure and induce the discharge of the confined aquifer. The study results indicated that aquifer characteristics play an important role in determining groundwater-level changes during and after earthquakes.

  19. Uncertainties in geologic disposal of high-level wastes - groundwater transport of radionuclides and radiological consequences

    International Nuclear Information System (INIS)

    Kocher, D.C.; Sjoreen, A.L.; Bard, C.S.

    1983-01-01

    The analysis for radionuclide transport in groundwater considers models and methods for characterizing (1) the present geologic environment and its future evolution due to natural geologic processes and to repository development and waste emplacement, (2) groundwater hydrology, (3) radionuclide geochemistry, and (4) the interactions among these phenomena. The discussion of groundwater transport focuses on the nature of the sources of uncertainty rather than on quantitative estimates of their magnitude, because of the lack of evidence that current models can provide realistic quantitative predictions of radionuclide transport in groundwater for expected repository environments. The analysis for the long-term health risk to man following releases of long-lived radionuclides to the biosphere is more quantitative and involves estimates of uncertainties in (1) radionuclide concentrations in man's exposure environment, (2) radionuclide intake by exposed individuals per unit concentration in the environment, (3) the dose per unit intake, (4) the number of exposed individuals, and (5) the health risk per unit dose. For the important long-lived radionuclides in high-level waste, uncertainties in most of the different components of a calculation of individual and collective dose per unit release appear to be no more than two or three orders of magnitude; these uncertainties are certainly much less than uncertainties in predicting groundwater transport of radionuclides between a repository and the biosphere. Several limitations in current models for predicting the health risk to man per unit release to the biosphere are discussed

  20. Comparison of 1972 and 1996 water levels in the Goleta central ground-water subbasin, Santa Barbara County, California

    Science.gov (United States)

    Kaehler, Charles A.; Pratt, David A.; Paybins, Katherine S.

    1997-01-01

    Ground-water levels for 1996 were compared with 1972 water levels to determine if a "drought buffer" currently exists. The drought buffer was defined previously, in a litigated settlement involving the Goleta Water District, as the 1972 water level in the Central ground-water subbasin. To make this deter mination, a network of 15 well sites was selected, water levels were measured monthly from April through December 1996, and the 1996 water-level data were compared with1972 data. The study was done in cooperation with the Goleta Water District. The 1972-1996 water-level-altitude changes for corresponding months of the comparison years were averaged for each network well. These averaged changes ranged from a rise of 9.4 ft for well 2N2 to a decline of 45.0 ft for well 8K8. The results of the comparison indicate a rise in water level at 1 site (well 2N2) and a decline at 14 sites. The mean of the 14 negative average values was a decline of 24.0 ft. The altitude of the bottom of well 2N2 was higher than the bottom altitudes at the other network sites, and this well is located a few feet from a fault that acts as a hydrologic barrier. The results of the water-level comparison for the Central subbasin were influenced to some unknown degree by the areal distribution of the set of wells selected for the network and the vertical dis tribution of the perforated intervals of the wells. For this reason, the mean water-level change--a decline of 21.8 ft--calculated from the averages of the month-to-month changes for the 15 network sites, should be used with caution. In addition, the number of usable individual monthly comparison measurements available for an individual site ranged from one to nine, and averaged six. Therefore, a weighted mean of the monthly averages was calculated on the basis of the number of comparison measurements available for each site. The weighted mean is a decline of 20.9 ft. All Central subbasin wells that were idle (that is, were not being pumped

  1. Transient simulation of groundwater levels within a sandbar of the Colorado River, Marble Canyon, Arizona, 2004

    Science.gov (United States)

    Sabol, Thomas A.; Springer, Abraham E.

    2013-01-01

    Seepage erosion and mass failure of emergent sandy deposits along the Colorado River in Grand Canyon National Park, Arizona, are a function of the elevation of groundwater in the sandbar, fluctuations in river stage, the exfiltration of water from the bar face, and the slope of the bar face. In this study, a generalized three-dimensional numerical model was developed to predict the time-varying groundwater level, within the bar face region of a freshly deposited eddy sandbar, as a function of river stage. Model verification from two transient simulations demonstrates the ability of the model to predict groundwater levels within the onshore portion of the sandbar face across a range of conditions. Use of this generalized model is applicable across a range of typical eddy sandbar deposits in diverse settings. The ability to predict the groundwater level at the onshore end of the sandbar face is essential for both physical and numerical modeling efforts focusing on the erosion and mass failure of eddy sandbars downstream of Glen Canyon Dam along the Colorado River.

  2. THE STUDY OF CHANGES IN ARDABIL PLAIN GROUNDWATER LEVEL USING GIS

    Directory of Open Access Journals (Sweden)

    Javad Zare Aghbolagh

    2016-03-01

    Full Text Available Uncontrolled exploitation of groundwater in many parts of the world has led to a sharp drop in groundwater levels. In this study, changes in Ardabil plain groundwater level were studied using geographic information system (GIS. For this purpose, the interpolation table method was used, the intrinsic data as table data of piezo metric wells was used. In order to implement the model, the Majol Geoestatical in geographic information system software was used. The data entered as regions into the geographic information system, and then done for the entire zoning area, due to zoning 8 models, the IDW, GPI, RBF, LPI, KO, KS, KU and EBK in geostatical extension were evaluated. The ordinary kriging method (KO with the lowest RMSE, was determined as the most accurate one, and finally, as the ultimate method for zoning and map providing for the changes in groundwater levels drop of the region. The results of classification showed that the biggest drop of about 40 meters was in the areas close to the southeastern parts of the study region and in other areas, little changes were observed, this rate of the change and decline in some parts of the desert like southern regions is very tangible and specified.

  3. Friendship network position and salivary cortisol levels.

    Science.gov (United States)

    Kornienko, Olga; Clemans, Katherine H; Out, Dorothée; Granger, Douglas A

    2013-01-01

    We employed a social network analysis approach to examine the associations between friendship network position and cortisol levels. The sample consisted of 74 first-year students (93% female, ages 22-38 years, M = 27) from a highly competitive, accelerated Nursing program. Participants completed questionnaires online, and the entire group met at one time to complete a series of sociometric nominations and donated a saliva sample. Saliva was later assayed for cortisol. Metrics derived from directed friendship nominations indexed each student's friendship network status regarding popularity, gregariousness, and degree of interconnectedness. Results revealed that (1) individuals with lower gregariousness status (i.e., lowest number of outgoing ties) had higher cortisol levels, and (2) individuals with higher popularity status (i.e., higher numbers of incoming ties) had higher cortisol levels. Popularity and gregariousness-based network status is significantly associated with hypothalamic-pituitary-adrenal axis activity. Implications for prevailing theories of the social determinants of individual differences in biological sensitivity and susceptibility to context are discussed.

  4. A Comparison of Seasonal Patterns Observed in ERS 1 / 2 Differential InSAR, Groundwater Level Data, and Groundwater Production Data in Reno, Nevada, USA.

    Science.gov (United States)

    Oppliger, G. L.; Goudy, C.; Widmer, M.

    2005-12-01

    We report on a comparison of repeating seasonal patterns observed in ERS 1 / 2 differential InSAR, (D-InSAR) groundwater level (GWL) data, and water production volume data in Reno, Nevada, USA. Over the 1992-2002 study period we found municipal groundwater utilization in the Reno study area was associated with centimeter and sub-centimeter surface elevation changes which are distributed over aquifer related zones several kilometers in width. In the central Reno area observations define two active anomaly areas which show cyclical surface deflation and inflation with elevation changes of 10 to 30 millimeters over one to nine years. Seasonal groundwater level change associated with these D-InSAR features ranged between 0.3 and 3 meters. Some D-InSAR pattern perimeters are localized by geologic structure while others are more mobile. Most surface deflation appears to be periodically restored by natural and managed aquifer recharge. The area's of active surface inflation-deflation nominally correspond with the area's most significantly utilized groundwater aquifers. To evaluate evidence for the direct relation between D-InSAR and groundwater production in the study area, comparisons between 1992-2002 groundwater levels, production rates and D-InSAR surface inflation-deflation features were developed. Groundwater level change maps showed good direct correlations with D-InSAR observations only in areas where the GWL changes were relatively large (~10 meters), spatially uniform and sustained over several years. Several factors probably contribute to the weak correlation of many GWL's and D-InSAR features including: incomplete GWL coverages, GWL monitoring data representing different aquifer horizons, proximity to production wells, delayed development of aquifer volume change when water levels are altered, and lateral change in aquifer composition. Consistency of the D-InSAR features suggests atmospheric artifacts were not the source of the discrepancies. Some of the

  5. Forecasting Water Levels Using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Shreenivas N. Londhe

    2011-06-01

    Full Text Available For all Ocean related activities it is necessary to predict the actual water levels as accurate as possible. The present work aims at predicting the water levels with a lead time of few hours to a day using the technique of artificial neural networks. Instead of using the previous and current values of observed water level time series directly as input and output the water level anomaly (difference between the observed water level and harmonically predicted tidal level is calculated for each hour and the ANN model is developed using this time series. The network predicted anomaly is then added to harmonic tidal level to predict the water levels. The exercise is carried out at six locations, two in The Gulf of Mexico, two in The Gulf of Maine and two in The Gulf of Alaska along the USA coastline. The ANN models performed reasonably well for all forecasting intervals at all the locations. The ANN models were also run in real time mode for a period of eight months. Considering the hurricane season in Gulf of Mexico the models were also tested particularly during hurricanes.

  6. An analysis of potential impacts to the groundwater monitoring networks in the Central Plateau. Revision 0

    International Nuclear Information System (INIS)

    1996-01-01

    This report presents the results of an evaluation of potential impacts to the four groundwater monitoring projects operating in the Central Plateau of the Hanford Site. It specifically fulfills Milestone M-15-81A of the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement). Milestone M-15-81A specifies the evaluation of the potential impacts to the groundwater monitoring well systems in the Central Plateau caused by the following activities: reduction of liquids discharged to soil, proposed and operational liquid treatment facilities, and proposed pump-and-treat systems. For this report, an open-quotes impactclose quotes is defined as a restriction of the ability to draw samples from a well and/or a reduction of the ability of a monitoring well to meet its intended purpose (such as the detection of contaminant seepage from a facility). Approximately 20% (74 wells) of the groundwater monitoring wells potentially will experience sampling problems by the year 2005 due to the declining water table in the Central Plateau. Reduction of discharges to the B Pond complex and operation of the Treated Effluent Disposal System will directly cause four additional wells to potentially experience sampling problems. Approximately 90 monitoring wells (35 of which are Resource Conservation and Recovery Act of 1976 [RCRA] wells) will be potentially affected by the operation of pump-and-treat systems in the 200 West Area. Most of the impacts will be caused by local changes to groundwater flow directions that will potentially reduce the ability of the RCRA well network to monitor a limited number of RCRA facilities

  7. Atoll groundwater movement and its response to climatic and sea-level fluctuations

    Science.gov (United States)

    Oberle, Ferdinand; Swarzenski, Peter W.; Storlazzi, Curt

    2017-01-01

    Groundwater resources of low-lying atoll islands are threatened due to short-term and long-term changes in rainfall, wave climate, and sea level. A better understanding of how these forcings affect the limited groundwater resources was explored on Roi-Namur in the Republic of the Marshall Islands. As part of a 16-month study, a rarely recorded island-overwash event occurred and the island’s aquifer’s response was measured. The findings suggest that small-scale overwash events cause an increase in salinity of the freshwater lens that returns to pre-overwash conditions within one month. The overwash event is addressed in the context of climate-related local sea-level change, which suggests that overwash events and associated degradations in freshwater resources are likely to increase in severity in the future due to projected rises in sea level. Other forcings, such as severe rainfall events, were shown to have caused a sudden freshening of the aquifer, with salinity levels retuning to pre-rainfall levels within three months. Tidal forcing of the freshwater lens was observed in electrical resistivity profiles, high-resolution conductivity, groundwater-level well measurements and through submarine groundwater discharge calculations. Depth-specific geochemical pore water measurements further assessed and confirmed the distinct boundaries between fresh and saline water masses in the aquifer. The identification of the freshwater lens’ saline boundaries is essential for a quantitative evaluation of the aquifers freshwater resources and help understand how these resources may be impacted by climate change and anthropogenic activities.

  8. Atoll Groundwater Movement and Its Response to Climatic and Sea-Level Fluctuations

    Directory of Open Access Journals (Sweden)

    Ferdinand K. J. Oberle

    2017-08-01

    Full Text Available Groundwater resources of low-lying atoll islands are threatened due to short-term and long-term changes in rainfall, wave climate, and sea level. A better understanding of how these forcings affect the limited groundwater resources was explored on Roi-Namur in the Republic of the Marshall Islands. As part of a 16-month study, a rarely recorded island-overwash event occurred and the island’s aquifer’s response was measured. The findings suggest that small-scale overwash events cause an increase in salinity of the freshwater lens that returns to pre-overwash conditions within one month. The overwash event is addressed in the context of climate-related local sea-level change, which suggests that overwash events and associated degradations in freshwater resources are likely to increase in severity in the future due to projected rises in sea level. Other forcings, such as severe rainfall events, were shown to have caused a sudden freshening of the aquifer, with salinity levels retuning to pre-rainfall levels within three months. Tidal forcing of the freshwater lens was observed in electrical resistivity profiles, high-resolution conductivity, groundwater-level well measurements and through submarine groundwater discharge calculations. Depth-specific geochemical pore water measurements further assessed and confirmed the distinct boundaries between fresh and saline water masses in the aquifer. The identification of the freshwater lens’ saline boundaries is essential for a quantitative evaluation of the aquifers freshwater resources and help understand how these resources may be impacted by climate change and anthropogenic activities.

  9. Groundwater geochemistry near the storage sites of low-level radioactive waste: Implications for uranium migration

    Energy Technology Data Exchange (ETDEWEB)

    Gaskova, Olga L.; Boguslavsky, Anatoly E. [Institute of Geology and Mineralogy SB RAS, Ac. Koptyug prosp. 3, Novosibirsk 630090 (Russian Federation)

    2013-07-01

    This paper presents results of detailed sampling of groundwater and surface water near the storage sites of radioactive waste from the Electrochemical Plant ECP (Zelenogorsk, Krasnoyarsk region, Russia) and the Angarsk Electrolysis Chemical Complex AEC (Angarsk, Irkutsk region, Russia), both of which have produced enriched uranium since 1960's. The liquid (LRW) and solid (SRW) radioactive wastes belong to the category of low-level activity waste. The main result is that the uranium is below the recommended MPC for drinking waters in all types of groundwater around the sludge of ECP and AEC. But alkaline nitrate solutions have been penetrating and spreading into the aquifers under the LRW sludge pits. According to our calculations, redox conditions in the groundwater influenced by discharge are controlled by the couple NO{sub 3}{sup -}/NO{sub 2}{sup -} that facilitates U(VI) migration. The groundwater under SRW repositories is distinguished by its low mineralization and neutral pH. Co-contaminants, such as Mo, V, and Zr may serve as markers of techno-genous contamination in storage sites of the LRW sludge. (authors)

  10. Region-scale groundwater flow modelling of generic high level waste disposal sites

    International Nuclear Information System (INIS)

    Metcalfe, D.

    1996-02-01

    Regional-scale groundwater flow modelling analyses are performed on generic high level waste (HLW) disposal sites to assess the extent to which a large crystalline rock mass such as a pluton or batholith can be expected to contain and isolate HLW in terms of hydraulic considerations, for a variety of geologic and hydrogeologic conditions. The two-dimensional cross-sectional conceptual models of generic HLW disposal sites are evaluated using SWIFT III, which is a finite-difference flow and transport code. All steps leading to the final results and conclusions are incorporated in this report. The available data and information on geological and hydrogeologic conditions in plutons and batholiths are summarized. The generic conceptual models developed from this information are defined in terms of the finite difference grid, the geologic and hydrogeologic properties and the hydrologic boundary conditions used. The modelled results are described with contour maps showing the modelled head fields, groundwater flow paths and travel times and groundwater flux rates within the modelled systems. The results of the modelling analyses are used to develop general conclusions on the scales and patterns of groundwater flow in granitic plutons and batholiths. The conclusions focus on geologic and hydrogeologic characteristics that can result in favourable conditions, in terms of hydraulic considerations, for a HLW repository. (author) 43 refs., 9 tabs., 40 figs

  11. Climate change impact on groundwater levels in the Guarani Aquifer outcrop zone

    Science.gov (United States)

    Melo, D. D.; Wendland, E.

    2013-12-01

    The unsustainable use of groundwater in many countries might cause water availability restrictions in the future. Such issue is likely to worsen due to predicted climate changes for the incoming decades. As numerous studies suggest, aquifers recharge rates will be affected as a result of climate change. The Guarani Aquifer System (GAS) is one of the most important transboundary aquifer in the world, providing drinkable water for millions of people in four South American countries (Brazil, Argentina, Uruguay and Paraguay). Considering the GAS relevance and how its recharge rates might be altered by climatic conditions anomalies, the objective of this work is to assess possible climate changes impacts on groundwater levels in this aquifer outcrop zone. Global Climate Models' (GCM) outputs were used as inputs in a transient flux groundwater model created using the software SPA (Simulation of Process in Aquifers), enabling groundwater table fluctuation to be evaluated under distinct climatic scenarios. Six monitoring wells, located in a representative basin (Ribeirão da Onça basin) inside a GAS outcrop zone (ROB), provided water table measurements between 2004 and 2011 to calibrate the groundwater model. Using observed climatic data, a water budget method was applied to estimate recharge in different types of land uses. Statistically downscaled future climate scenarios were used as inputs for that same recharge model, which provided data for running SPA under those scenarios. The results show that most of the GCMs used here predict temperature arises over 275,15 K and major monthly rainfall mean changes to take place in the dry season. During wet seasons, those means might experience around 50% decrease. The transient model results indicate that water table variations, derived from around 70% of the climate scenarios, would vary below those measured between 2004 and 2011. Among the thirteen GCMs considered in this work, only four of them predicted more extreme

  12. Forecasting monthly groundwater level fluctuations in coastal aquifers using hybrid Wavelet packet–Support vector regression

    Directory of Open Access Journals (Sweden)

    N. Sujay Raghavendra

    2015-12-01

    Full Text Available This research demonstrates the state-of-the-art capability of Wavelet packet analysis in improving the forecasting efficiency of Support vector regression (SVR through the development of a novel hybrid Wavelet packet–Support vector regression (WP–SVR model for forecasting monthly groundwater level fluctuations observed in three shallow unconfined coastal aquifers. The Sequential Minimal Optimization Algorithm-based SVR model is also employed for comparative study with WP–SVR model. The input variables used for modeling were monthly time series of total rainfall, average temperature, mean tide level, and past groundwater level observations recorded during the period 1996–2006 at three observation wells located near Mangalore, India. The Radial Basis function is employed as a kernel function during SVR modeling. Model parameters are calibrated using the first seven years of data, and the remaining three years data are used for model validation using various input combinations. The performance of both the SVR and WP–SVR models is assessed using different statistical indices. From the comparative result analysis of the developed models, it can be seen that WP–SVR model outperforms the classic SVR model in predicting groundwater levels at all the three well locations (e.g. NRMSE(WP–SVR = 7.14, NRMSE(SVR = 12.27; NSE(WP–SVR = 0.91, NSE(SVR = 0.8 during the test phase with respect to well location at Surathkal. Therefore, using the WP–SVR model is highly acceptable for modeling and forecasting of groundwater level fluctuations.

  13. Groundwater levels and water-quality observations pertaining to the Austin Group, Bexar County, Texas, 2009-11

    Science.gov (United States)

    Banta, J.R.; Clark, Allan K.

    2012-01-01

    The U.S. Geological Survey, in cooperation with the San Antonio Water System, examined groundwater-level altitudes (groundwater levels) and water-quality data pertaining to the Austin Group in Bexar County, Texas, during 2009–11. Hydrologic data collected included daily mean groundwater levels collected at seven sites in the study area. Water-quality samples were collected at six sites in the study area and analyzed for major ions, nutrients, trace elements, organic carbon, and stable isotopes. The resulting datasets were examined for similarities between sites as well as similarities to data from the Edwards aquifer in Bexar County, Tex. Similarities in the groundwater levels between sites completed in the Austin Group and site J (State well AY-68-37-203; hereafter referred to as the “Bexar County index well”) which is completed in the Edwards aquifer might be indicative of groundwater interactions between the two hydrologic units as a result of nearby faulting or conduit flow. The groundwater levels measured at the sites in the study area exhibited varying degrees of similarity to the Bexar County index well. Groundwater levels at site A (State well AY-68-36-136) exhibited similar patterns as those at the Bexar County index well, but the hydrographs of groundwater levels were different in shape and magnitude in response to precipitation and groundwater pumping, and at times slightly offset in time. The groundwater level patterns measured at sites C, D, and E (State wells AY-68-29-513, AY-68-29-514, and AY-68-29-512, respectively) were not similar to those measured at the Bexar County index well. Groundwater levels at site F (State well AY-68-29-819) exhibited general similarities as those observed at the Bexar County index well; however, there were several periods of notable groundwater-level drawdowns at site F that were not evident at the Bexar County index well. These drawdowns were likely because of pumping from the well at site F. The groundwater

  14. Profiling micro-organic contaminants in groundwater using multi-level piezometers

    OpenAIRE

    White, Debbie; Lapworth, Dan; Stuart, Marianne; Williams, Peter

    2015-01-01

    The presence of micro-organic pollutants, including ‘emerging contaminants’ within groundwater is of increasing interest. Robust protocols are required to minimise the introduction of contamination during the sampling process. Below we discuss the sampling protocols used to reduce inputs of plasticisers during the sampling process, as well as the techniques used to characterise the distribution of micro-organic pollutants in the subsurface. In this study multi-level piezometers...

  15. Analysis of the applicability of geophysical methods and computer modelling in determining groundwater level

    Science.gov (United States)

    Czaja, Klaudia; Matula, Rafal

    2014-05-01

    The paper presents analysis of the possibilities of application geophysical methods to investigation groundwater conditions. In this paper groundwater is defined as liquid water flowing through shallow aquifers. Groundwater conditions are described through the distribution of permeable layers (like sand, gravel, fractured rock) and impermeable or low-permeable layers (like clay, till, solid rock) in the subsurface. GPR (Ground Penetrating Radar), ERT(Electrical Resistivity Tomography), VES (Vertical Electric Soundings) and seismic reflection, refraction and MASW (Multichannel Analysis of Surface Waves) belong to non - invasive, surface, geophysical methods. Due to differences in physical parameters like dielectric constant, resistivity, density and elastic properties for saturated and saturated zones it is possible to use geophysical techniques for groundwater investigations. Few programmes for GPR, ERT, VES and seismic modelling were applied in order to verify and compare results. Models differ in values of physical parameters such as dielectric constant, electrical conductivity, P and S-wave velocity and the density, layers thickness and the depth of occurrence of the groundwater level. Obtained results for computer modelling for GPR and seismic methods and interpretation of test field measurements are presented. In all of this methods vertical resolution is the most important issue in groundwater investigations. This require proper measurement methodology e.g. antennas with frequencies high enough, Wenner array in electrical surveys, proper geometry for seismic studies. Seismic velocities of unconsolidated rocks like sand and gravel are strongly influenced by porosity and water saturation. No influence of water saturation degree on seismic velocities is observed below a value of about 90% water saturation. A further saturation increase leads to a strong increase of P-wave velocity and a slight decrease of S-wave velocity. But in case of few models only the

  16. Influence of seasonal variations in sea level on the salinity regime of a coastal groundwater-fed wetland.

    Science.gov (United States)

    Wood, Cameron; Harrington, Glenn A

    2015-01-01

    Seasonal variations in sea level are often neglected in studies of coastal aquifers; however, they may have important controls on processes such as submarine groundwater discharge, sea water intrusion, and groundwater discharge to coastal springs and wetlands. We investigated seasonal variations in salinity in a groundwater-fed coastal wetland (the RAMSAR listed Piccaninnie Ponds in South Australia) and found that salinity peaked during winter, coincident with seasonal sea level peaks. Closer examination of salinity variations revealed a relationship between changes in sea level and changes in salinity, indicating that sea level-driven movement of the fresh water-sea water interface influences the salinity of discharging groundwater in the wetland. Moreover, the seasonal control of sea level on wetland salinity seems to override the influence of seasonal recharge. A two-dimensional variable density model helped validate this conceptual model of coastal groundwater discharge by showing that fluctuations in groundwater salinity in a coastal aquifer can be driven by a seasonal coastal boundary condition in spite of seasonal recharge/discharge dynamics. Because seasonal variations in sea level and coastal wetlands are ubiquitous throughout the world, these findings have important implications for monitoring and management of coastal groundwater-dependent ecosystems. © 2014, National Ground Water Association.

  17. Water-level changes and directions of ground-water flow in the shallow aquifer, Fallon area, Churchill County, Nevada

    Science.gov (United States)

    Seiler, R.L.; Allander, K.K.

    1993-01-01

    The Truckee-Carson-Pyramid Lake Water Rights Settlement Act of 1990 directed the U.S. Fish and Wildlife Service to acquire water rights for wetland areas in the Carson Desert, Nevada. The public is concerned that htis acquisition of water rights and delivery of the water directly to wildlife areas would result in less recharge to the shallow ground water in the Fallon area and cause domestic wells to go dry. In January 1992, the U.S. Geological Survey, in cooperation with U.S. Fish and Wildlife Service, began a study of the shallow ground-water system in the Fallon area in Churchill County, Nevada. A network of 126 wells in the study area was monitored. Between January and November 1992, water levels in most wells declined, usually less than 2 feet. The maximum measured decline over this period was 2.68 feet in a well near Stillwater Marsh. Between April and July, however, water levels rose in irrigated areas, typically 1 to 2 feet. Newlands Project water deliveries to the study area began soon after the turn of the century. Since then, water levels have risen more than 15 feet across much of the study area. Water lost from unlined irrigtiaon canals caused the stage in Big Soda Lake to rise nearly 60 feet; ground-water levels near the lake have risen 30 to 40 feet. The depth to water in most irrigated areas is now less than 10 feet. The altitude of the water table ranges from 4.025 feet above sea level 11 miles west of Fallon to 3,865 feet in the Stillwater Marsh area. Ground water flows eastward and divides; some flow goes to the northeast toward the Carson Sink and Stillwater areas, and some goes southeastward to Carson Lake.

  18. A Multiple-Iterated Dual Control Model for Groundwater Exploitation and Water Level Based on the Optimal Allocation Model of Water Resources

    Directory of Open Access Journals (Sweden)

    Junqiu Liu

    2018-04-01

    Full Text Available In order to mitigate environmental and ecological impacts resulting from groundwater overexploitation, we developed a multiple-iterated dual control model consisting of four modules for groundwater exploitation and water level. First, a water resources allocation model integrating calculation module of groundwater allowable withdrawal was built to predict future groundwater recharge and discharge. Then, the results were input into groundwater numerical model to simulate water levels. Groundwater exploitation was continuously optimized using the critical groundwater level as the feedback, and a groundwater multiple-iterated technique was applied to the feedback process. The proposed model was successfully applied to a typical region in Shenyang in northeast China. Results showed the groundwater numerical model was verified in simulating water levels, with a mean absolute error of 0.44 m, an average relative error of 1.33%, and a root-mean-square error of 0.46 m. The groundwater exploitation reduced from 290.33 million m3 to 116.76 million m3 and the average water level recovered from 34.27 m to 34.72 m in planning year. Finally, we proposed the strategies for water resources management in which the water levels should be controlled within the critical groundwater level. The developed model provides a promising approach for water resources allocation and sustainable groundwater management, especially for those regions with overexploited groundwater.

  19. Assessment of groundwater level estimation uncertainty using sequential Gaussian simulation and Bayesian bootstrapping

    Science.gov (United States)

    Varouchakis, Emmanouil; Hristopulos, Dionissios

    2015-04-01

    Space-time geostatistical approaches can improve the reliability of dynamic groundwater level models in areas with limited spatial and temporal data. Space-time residual Kriging (STRK) is a reliable method for spatiotemporal interpolation that can incorporate auxiliary information. The method usually leads to an underestimation of the prediction uncertainty. The uncertainty of spatiotemporal models is usually estimated by determining the space-time Kriging variance or by means of cross validation analysis. For de-trended data the former is not usually applied when complex spatiotemporal trend functions are assigned. A Bayesian approach based on the bootstrap idea and sequential Gaussian simulation are employed to determine the uncertainty of the spatiotemporal model (trend and covariance) parameters. These stochastic modelling approaches produce multiple realizations, rank the prediction results on the basis of specified criteria and capture the range of the uncertainty. The correlation of the spatiotemporal residuals is modeled using a non-separable space-time variogram based on the Spartan covariance family (Hristopulos and Elogne 2007, Varouchakis and Hristopulos 2013). We apply these simulation methods to investigate the uncertainty of groundwater level variations. The available dataset consists of bi-annual (dry and wet hydrological period) groundwater level measurements in 15 monitoring locations for the time period 1981 to 2010. The space-time trend function is approximated using a physical law that governs the groundwater flow in the aquifer in the presence of pumping. The main objective of this research is to compare the performance of two simulation methods for prediction uncertainty estimation. In addition, we investigate the performance of the Spartan spatiotemporal covariance function for spatiotemporal geostatistical analysis. Hristopulos, D.T. and Elogne, S.N. 2007. Analytic properties and covariance functions for a new class of generalized Gibbs

  20. Comparison of different methods to assess natural backgrond levels in groundwater bodies in southern Europe

    Science.gov (United States)

    Preziosi, Elisabetta; Parrone, Daniele; Ghergo, Stefano; Ducci, Daniela; Sellerino, Mariangela; Condesso de Melo, Maria Teresa; Oliveira, Juana; Ribeiro, Luis

    2014-05-01

    The assessment of the natural background levels (NBLs) of a substance or element is important to distinguish anthropogenic pollution from contamination of natural origin in groundwater bodies. NBLs are the result of different atmospheric, geological, chemical and biological interaction processes during groundwater infiltration and circulation. Rainfall composition, water-rock interactions in both vadose and saturated zone, exchanges with other water bodies and residence time also contribute to determine the groundwater natural composition. Nowadays there are different methods to assess NBLs but the main concern is that they may provide different results. In the European legislative context, the Groundwater Directive (2006/118/EC) requests to EU Member States to derive appropriate threshold values (TV) for several potentially harmful substances, taking into account NBLs when necessary, in order to assess the chemical status of groundwater bodies. In the framework of a common project between Italy (CNR) and Portugal (FCT), several groundwater bodies were taken into account in different regions of Italy (Latium and Campania) and Portugal. The general objective is the definition of a sound comprehensive methodology for NBL assessment at groundwater body scale, suitable to different hydrogeological settings through comparing diverse case studies and different approaches. The Italian case studies are located in volcanic or volcano-sedimentary geological contexts, where high concentrations of substances such as As, F, Fe, Mn among others in groundwater are well known. The Portuguese case studies are located in carbonate and porous media aquifers. Several data sets were explored with the use of statistical as well as mathematical procedures in order to determine a threshold between natural and anthropogenic concentration. Today essentially two groups of methods are proposed, the first ascribed to the probability plots (PP method), the second based on the selection of the

  1. Effort levels of the partners in networked manufacturing

    Science.gov (United States)

    Chai, G. R.; Cai, Z.; Su, Y. N.; Zong, S. L.; Zhai, G. Y.; Jia, J. H.

    2017-08-01

    Compared with traditional manufacturing mode, could networked manufacturing improve effort levels of the partners? What factors will affect effort level of the partners? How to encourage the partners to improve their effort levels? To answer these questions, we introduce network effect coefficient to build effort level model of the partners in networked manufacturing. The results show that (1) with the increase of the network effect in networked manufacturing, the actual effort level can go beyond the ideal level of traditional manufacturing. (2) Profit allocation based on marginal contribution rate would help improve effort levels of the partners in networked manufacturing. (3) The partners in networked manufacturing who wishes to have a larger distribution ratio must make a higher effort level, and enterprises with insufficient effort should be terminated in networked manufacturing.

  2. Uncertainty of simulated groundwater levels arising from stochastic transient climate change scenarios

    Science.gov (United States)

    Goderniaux, Pascal; Brouyère, Serge; Blenkinsop, Stephen; Burton, Aidan; Fowler, Hayley; Dassargues, Alain

    2010-05-01

    applied not only to the mean of climatic variables, but also across the statistical distributions of these variables. This is important as these distributions are expected to change in the future, with more extreme rainfall events, separated by longer dry periods. (2) The novel approach used in this study can simulate transient climate change from 2010 to 2085, rather than time series representative of a stationary climate for the period 2071-2100. (3) The weather generator is used to generate a large number of equiprobable climate change scenarios for each RCM, representative of the natural variability of the weather. All of these scenarios are applied as input to the Geer basin model to assess the projected impact of climate change on groundwater levels, the uncertainty arising for different RCM projections and the uncertainty linked to natural climatic variability. Using the output results from all scenarios, 95% confidence intervals are calculated for each year and month between 2010 and 2085. The climate change scenarios for the Geer basin model predict hotter and drier summers and warmer and wetter winters. Considering the results of this study, it is very likely that groundwater levels and surface flow rates in the Geer basin will decrease by the end of the century. This is of concern because it also means that groundwater quantities available for abstraction will also decrease. However, this study also shows that the uncertainty of these projections is relatively large compared to the projected changes so that it remains difficult to confidently determine the magnitude of the decrease. The use and combination of an integrated surface - subsurface model and stochastic climate change scenarios has never been used in previous climate change impact studies on groundwater resources. It constitutes an innovation and is an important tool for helping water managers to take decisions.

  3. Prediction of Groundwater Arsenic Contamination using Geographic Information System and Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Md. Moqbul Hossain

    2013-01-01

    Full Text Available Ground water arsenic contamination is a well known health and environmental problem in Bangladesh. Sources of this heavy metal are known to be geogenic, however, the processes of its release into groundwater are poorly understood phenomena. In quest of mitigation of the problem it is necessary to predict probable contamination before it causes any damage to human health. Hence our research has been carried out to find the factor relations of arsenic contamination and develop an arsenic contamination prediction model. Researchers have generally agreed that the elevated concentration of arsenic is affected by several factors such as soil reaction (pH, organic matter content, geology, iron content, etc. However, the variability of concentration within short lateral and vertical intervals, and the inter-relationships of variables among themselves, make the statistical analyses highly non-linear and difficult to converge with a meaningful relationship. Artificial Neural Networks (ANN comes in handy for such a black box type problem. This research uses Back propagation Neural Networks (BPNN to train and validate the data derived from Geographic Information System (GIS spatial distribution grids. The neural network architecture with (6-20-1 pattern was able to predict the arsenic concentration with reasonable accuracy.

  4. Well-Construction, Water-Level, and Water-Quality Data for Ground-Water Monitoring Wells for the J4 Hydrogeologic Study, Arnold Air Force Base, Tennessee

    National Research Council Canada - National Science Library

    Haugh, Connor J

    1996-01-01

    ...) in Coffee County, Tennessee. The wells ranged from 28 to 289 feet deep and were installed to provide information on subsurface lithology, aquifer characteristics, ground-water levels, and ground-water quality...

  5. Observations and analysis of free groundwater levels and groundwater pressure in landslide slopes. Jisuberi shamen no jiyu chikasuii, chikasuiatsu no kansoku to kaiseki ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, S; Nakano, T [Niigata Univ., Niigata (Japan). Faculty of Agriculture; Inaba, K [Niigata Univ., Niigata (Japan). Graduate School; Sato, O [Niigata Univ., Niigata (Japan)

    1991-12-25

    It is well known that the landslides in Tertiary systems abundantly found in Niigata Prefecture, etc., frequently occur especially in the snow melting season or the heavy rain season. For studying the occurrence of such landslides, exploration of the actual condition of groundwater and evaluation of the strength of earth are very important even when the landslide occurring mechanism can be presumed in a relatively simple way about the soil mechanics. Therefore, great importance is attached to the observation and investigation on the groundwater level and pressure at landslide sites and stability analyses have been actively performed. However, it is considered that several fundamental problems still exist in the method for estimating the groundwater level and pressure in landslide slopes from the observation method and data on groundwater levels and pressure (pore pressure). In this paper, these fundamental problems are examined on the basis of concrete observations made by the writers on landslide slopes at Matunoyamagoe and Higashimusikame landslide sites in Niigata Prefecture for the past several years. 6 ref., 6 figs., 2 tabs.

  6. Application of a modified conceptual rainfall-runoff model to simulation of groundwater level in an undefined watershed.

    Science.gov (United States)

    Hong, Nian; Hama, Takehide; Suenaga, Yuichi; Aqili, Sayed Waliullah; Huang, Xiaowu; Wei, Qiaoyan; Kawagoshi, Yasunori

    2016-01-15

    Groundwater level simulation models can help ensure the proper management and use of urban and rural water supply. In this paper, we propose a groundwater level tank model (GLTM) based on a conceptual rainfall-runoff model (tank model) to simulate fluctuations in groundwater level. The variables used in the simulations consist of daily rainfall and daily groundwater level, which were recorded between April 2011 and March 2015 at two representative observation wells in Kumamoto City, Japan. We determined the best-fit model parameters by root-mean-square error through use of the Shuffled Complex Evolution-University of Arizona algorithm on a simulated data set. Calibration and validation results were evaluated by their coefficients of determination, Nash-Sutcliffe efficiency coefficients, and root-mean-square error values. The GLTM provided accurate results in both the calibration and validation of fluctuations in groundwater level. The split sample test results indicate a good reliability. These results indicate that this model can provide a simple approach to the accurate simulation of groundwater levels. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Responses of Water and Salt Parameters to Groundwater Levels for Soil Columns Planted with Tamarix chinensis.

    Science.gov (United States)

    Xia, Jiangbao; Zhao, Ximei; Chen, Yinping; Fang, Ying; Zhao, Ziguo

    2016-01-01

    Groundwater is the main water resource for plant growth and development in the saline soil of the Yellow River Delta in China. To investigate the variabilities and distributions of soil water and salt contents at various groundwater level (GL), soil columns with planting Tamarix chinensis Lour were established at six different GL. The results demonstrated the following: With increasing GL, the relative soil water content (RWC) declined significantly, whereas the salt content (SC) and absolute soil solution concentration (CS) decreased after the initial increase in the different soil profiles. A GL of 1.2 m was the turning point for variations in the soil water and salt contents, and it represented the highest GL that could maintain the soil surface moist within the soil columns. Both the SC and CS reached the maximum levels in these different soil profiles at a GL of 1.2 m. With the raise of soil depth, the RWC increased significantly, whereas the SC increased after an initial decrease. The mean SC values reached 0.96% in the top soil layer; however, the rates at which the CS and RWC decreased with the GL were significantly reduced. The RWC and SC presented the greatest variations at the medium (0.9-1.2 m) and shallow water levels (0.6 m) respectively, whereas the CS presented the greatest variation at the deep water level (1.5-1.8 m).The RWC, SC and CS in the soil columns were all closely related to the GL. However, the correlations among the parameters varied greatly within different soil profiles, and the most accurate predictions of the GL were derived from the RWC in the shallow soil layer or the SC in the top soil layer. A GL at 1.5-1.8 m was moderate for planting T. chinensis seedlings under saline groundwater conditions.

  8. Responses of Water and Salt Parameters to Groundwater Levels for Soil Columns Planted with Tamarix chinensis.

    Directory of Open Access Journals (Sweden)

    Jiangbao Xia

    Full Text Available Groundwater is the main water resource for plant growth and development in the saline soil of the Yellow River Delta in China. To investigate the variabilities and distributions of soil water and salt contents at various groundwater level (GL, soil columns with planting Tamarix chinensis Lour were established at six different GL. The results demonstrated the following: With increasing GL, the relative soil water content (RWC declined significantly, whereas the salt content (SC and absolute soil solution concentration (CS decreased after the initial increase in the different soil profiles. A GL of 1.2 m was the turning point for variations in the soil water and salt contents, and it represented the highest GL that could maintain the soil surface moist within the soil columns. Both the SC and CS reached the maximum levels in these different soil profiles at a GL of 1.2 m. With the raise of soil depth, the RWC increased significantly, whereas the SC increased after an initial decrease. The mean SC values reached 0.96% in the top soil layer; however, the rates at which the CS and RWC decreased with the GL were significantly reduced. The RWC and SC presented the greatest variations at the medium (0.9-1.2 m and shallow water levels (0.6 m respectively, whereas the CS presented the greatest variation at the deep water level (1.5-1.8 m.The RWC, SC and CS in the soil columns were all closely related to the GL. However, the correlations among the parameters varied greatly within different soil profiles, and the most accurate predictions of the GL were derived from the RWC in the shallow soil layer or the SC in the top soil layer. A GL at 1.5-1.8 m was moderate for planting T. chinensis seedlings under saline groundwater conditions.

  9. Responses of Water and Salt Parameters to Groundwater Levels for Soil Columns Planted with Tamarix chinensis

    Science.gov (United States)

    Xia, Jiangbao; Zhao, Ximei; Chen, Yinping; Fang, Ying; Zhao, Ziguo

    2016-01-01

    Groundwater is the main water resource for plant growth and development in the saline soil of the Yellow River Delta in China. To investigate the variabilities and distributions of soil water and salt contents at various groundwater level (GL), soil columns with planting Tamarix chinensis Lour were established at six different GL. The results demonstrated the following: With increasing GL, the relative soil water content (RWC) declined significantly, whereas the salt content (SC) and absolute soil solution concentration (CS) decreased after the initial increase in the different soil profiles. A GL of 1.2 m was the turning point for variations in the soil water and salt contents, and it represented the highest GL that could maintain the soil surface moist within the soil columns. Both the SC and CS reached the maximum levels in these different soil profiles at a GL of 1.2 m. With the raise of soil depth, the RWC increased significantly, whereas the SC increased after an initial decrease. The mean SC values reached 0.96% in the top soil layer; however, the rates at which the CS and RWC decreased with the GL were significantly reduced. The RWC and SC presented the greatest variations at the medium (0.9–1.2 m) and shallow water levels (0.6 m) respectively, whereas the CS presented the greatest variation at the deep water level (1.5–1.8 m).The RWC, SC and CS in the soil columns were all closely related to the GL. However, the correlations among the parameters varied greatly within different soil profiles, and the most accurate predictions of the GL were derived from the RWC in the shallow soil layer or the SC in the top soil layer. A GL at 1.5–1.8 m was moderate for planting T. chinensis seedlings under saline groundwater conditions. PMID:26730602

  10. The thermal consequences of river-level variations in an urban groundwater body highly affected by groundwater heat pumps.

    Science.gov (United States)

    García-Gil, Alejandro; Vázquez-Suñe, Enric; Schneider, Eduardo Garrido; Sánchez-Navarro, José Ángel; Mateo-Lázaro, Jesús

    2014-07-01

    The extensive implementation of ground source heat pumps in urban aquifers is an important issue related to groundwater quality and the future economic feasibility of existent geothermal installations. Although many cities are in the immediate vicinity of large rivers, little is known about the thermal river-groundwater interaction at a kilometric-scale. The aim of this work is to evaluate the thermal impact of river water recharges induced by flood events into an urban alluvial aquifer anthropogenically influenced by geothermal exploitations. The present thermal state of an urban aquifer at a regional scale, including 27 groundwater heat pump installations, has been evaluated. The thermal impacts of these installations in the aquifer together with the thermal impacts from "cold" winter floods have also been spatially and temporally evaluated to ensure better geothermal management of the aquifer. The results showed a variable direct thermal impact from 0 to 6 °C depending on the groundwater-surface water interaction along the river trajectory. The thermal plumes far away from the riverbed also present minor indirect thermal impacts due to hydraulic gradient variations. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Relations between vegetation and water level in groundwater dependent terrestrial ecosystems (GWDTEs)

    DEFF Research Database (Denmark)

    Munch Johansen, Ole; Andersen, Dagmar Kappel; Ejrnæs, Rasmus

    2018-01-01

    , management and conservation of fens are constrained by limited knowledge on the relations between vegetation and measurable hydrological conditions. This study investigates the relations between vegetation and water level dynamics in groundwater dependent wetlands in Denmark. A total of 35 wetland sites...... across Denmark were included in the study. The sites represent a continuum of wetlands with respect to vegetation and hydrological conditions. Water level was measured continuously using pressure transducers at each site. Metrics expressing different hydrological characteristics, such as mean water level...... and low and high water level periods, were calculated based on the water level time series. A complete plant species list was recorded in plots covering 78.5 m2 at each site. Community metrics such as total number of species and the number of bryophytes were generated from the species lists and Ellenberg...

  12. Declining groundwater level caused by irrigation to row crops in the Lower Mississippi River Basin, Current Situation and Trends

    Science.gov (United States)

    Feng, G.; Gao, F.; Ouyang, Y.

    2017-12-01

    The Mississippi River is North America's largest river and the second largest watershed in the world. It flows over 3,700 km through America's heartland to the Gulf of Mexico. Over 3 million hectares in the Lower Mississippi River Basin represent irrigated cropland and 90 percent of those lands currently rely on the groundwater supply. The primary crops grown in this region are soybean, corn, cotton, and rice. Increased water withdrawals for irrigating those crops and stagnant recharging jeopardize the long-term availability of the aquifer and place irrigation agriculture in the region on an unsustainable path. The objectives of this study were to: 1) analyze the current groundwater level in the Lower Mississippi River Basin based on the water table depth observed by Yazoo Mississippi Delta Joint Water Management District from 2000 and 2016; 2) determine trends of change in groundwater level under conventional and groundwater saving irrigation management practices (ET or soil moisture based full irrigation scheduling using all groundwater or different percentages of ground and surface water). The coupled SWAT and MODFLOW model was applied to investigate the trends. Observed results showed that the groundwater level has declined from 33 to 26 m at an annual decrease rate of 0.4 m in the past 17 years. Simulated results revealed that the groundwater storage was decreased by 26 cm/month due to irrigation in crop season. It is promising that the groundwater storage was increased by 23 cm/month, sometimes even 60 cm/month in crop off-growing season because of recharge from rainfall. Our results suggest that alternative ET or soil moisture based groundwater saving irrigation scheduling with conjunctive use of surface water is a sustainable practice for irrigated agriculture in in the Lower Mississippi River Basin.

  13. Mapping groundwater level and aquifer storage variations from InSAR measurements in the Madrid aquifer, Central Spain

    Science.gov (United States)

    Béjar-Pizarro, Marta; Ezquerro, Pablo; Herrera, Gerardo; Tomás, Roberto; Guardiola-Albert, Carolina; Ruiz Hernández, José M.; Fernández Merodo, José A.; Marchamalo, Miguel; Martínez, Rubén

    2017-04-01

    Groundwater resources are under stress in many regions of the world and the future water supply for many populations, particularly in the driest places on Earth, is threatened. Future climatic conditions and population growth are expected to intensify the problem. Understanding the factors that control groundwater storage variation is crucial to mitigate its adverse consequences. In this work, we apply satellite-based measurements of ground deformation over the Tertiary detritic aquifer of Madrid (TDAM), Central Spain, to infer the spatio-temporal evolution of water levels and estimate groundwater storage variations. Specifically, we use Persistent Scatterer Interferometry (PSI) data during the period 1992-2010 and piezometric time series on 19 well sites covering the period 1997-2010 to build groundwater level maps and quantify groundwater storage variations. Our results reveal that groundwater storage loss occurred in two different periods, 1992-1999 and 2005-2010 and was mainly concentrated in a region of ∼200 km2. The presence of more compressible materials in that region combined with a long continuous water extraction can explain this volumetric deficit. This study illustrates how the combination of PSI and piezometric data can be used to detect small aquifers affected by groundwater storage loss helping to improve their sustainable management.

  14. Simulation of Groundwater-Level and Salinity Changes in the Eastern Shore, Virginia

    Science.gov (United States)

    Sanford, Ward E.; Pope, Jason P.; Nelms, David L.

    2009-01-01

    Groundwater-level and salinity changes have been simulated with a groundwater model developed and calibrated for the Eastern Shore of Virginia. The Eastern Shore is the southern part of the Delmarva Peninsula that is occupied by Accomack and Northampton Counties in Virginia. Groundwater is the sole source of freshwater to the Eastern Shore, and demands for water have been increasing from domestic, industrial, agricultural, and public-supply sectors of the economy. Thus, it is important that the groundwater supply be protected from overextraction and seawater intrusion. The best way for water managers to use all of the information available is usually to compile this information into a numerical model that can simulate the response of the system to current and future stresses. A detailed description of the geology, hydrogeology, and historical groundwater extractions was compiled and entered into the numerical model. The hydrogeologic framework is composed of a surficial aquifer under unconfined conditions, a set of three aquifers and associated overlying confining units under confined conditions (the upper, middle, and lower Yorktown-Eastover Formation), and an underlying confining unit (the St. Marys Formation). An estimate of the location and depths of two major paleochannels was also included in the framework of the model. Total withdrawals from industrial, commercial, public-supply, and some agricultural wells were compiled from the period 1900 through 2003. Reported pumpage from these sources increased dramatically during the 1960s and 70s, up to currently about 4 million gallons per day. Domestic withdrawals were estimated on the basis of population census districts and were assigned spatially to the model on the assumption that domestic users are located close to roads. A numerical model was created using the U.S. Geological Survey (USGS) code SEAWAT to simulate both water levels and concentrations of chloride (representing salinity). The model was

  15. Development og groundwater flow modeling techniques for the low-level radwaste disposal (III)

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Dae-Seok; Kim, Chun-Soo; Kim, Kyung-Soo; Park, Byung-Yoon; Koh, Yong-Kweon; Park, Hyun-Soo [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2000-12-01

    The project amis to establish the methodology of hydrogeologic assessment by the field application of the evaluation techniques gained and accumulated from the previous hydrogeological research works in Korea. The results of the project and their possible areas for application are (1) acquisition of detailed hydrogeologic information by using a borehole televiewer and a multipacker system, (2) establishing an integrated hydrogeological assessment method for fractured rocks, (3) acquisition of the fracture parameters for fracture modeling, (4) an inversion analysis of hydraulic parameters from fracture network modeling, (5) geostatistical methods for the spatial assignment of hydraulic parameters for fractured rocks, and (6) establishing the groundwater flow modeling procedure for a repository. 75 refs., 72 figs., 34 tabs. (Author)

  16. Development of groundwater flow modeling techniques for the low-level radwaste disposal(II)

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Dae Seok; Kim, Chun Soo; Kim, Kyung Su; Koh, Yong Kweon; Park, Byung Yoon; Hwang, Yong Soo; Park, Hyun Soo [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2000-01-01

    Field survey tasks including core drilling and hydraulic tests in the study site were carried out to assess the hydrogeological parameters used in the groundwater flow model. The site-specific hydrogeological system has characterized based on the fracture properties and hydrogeologic parameters as the following: - the spatial distribution of hydraulic conductivity by geostatistics - the relation of fracture properties to hydraulic conductivity - the effective permeability in a hydrogeologic unit. From the study results, it was recognized that the hydraulic conductivity in fractured rock masses was preferentially affected by aperture size of conductive fractures. The homogeneous REV scale and hydraulic tensor could be calculated from three dimensional discrete fracture network model. 31 refs., 56 figs., 16 tabs. (Author)

  17. Effects of Heterogeneity and Uncertainties in Sources and Initial and Boundary Conditions on Spatiotemporal Variations of Groundwater Levels

    Science.gov (United States)

    Zhang, Y. K.; Liang, X.

    2014-12-01

    Effects of aquifer heterogeneity and uncertainties in source/sink, and initial and boundary conditions in a groundwater flow model on the spatiotemporal variations of groundwater level, h(x,t), were investigated. Analytical solutions for the variance and covariance of h(x, t) in an unconfined aquifer described by a linearized Boussinesq equation with a white noise source/sink and a random transmissivity field were derived. It was found that in a typical aquifer the error in h(x,t) in early time is mainly caused by the random initial condition and the error reduces as time goes to reach a constant error in later time. The duration during which the effect of the random initial condition is significant may last a few hundred days in most aquifers. The constant error in groundwater in later time is due to the combined effects of the uncertain source/sink and flux boundary: the closer to the flux boundary, the larger the error. The error caused by the uncertain head boundary is limited in a narrow zone near the boundary but it remains more or less constant over time. The effect of the heterogeneity is to increase the variation of groundwater level and the maximum effect occurs close to the constant head boundary because of the linear mean hydraulic gradient. The correlation of groundwater level decreases with temporal interval and spatial distance. In addition, the heterogeneity enhances the correlation of groundwater level, especially at larger time intervals and small spatial distances.

  18. Regional groundwater chemical characteristics of Aqishan pre-selected site for high level radioactive waste repository and its hydrogeological significance

    International Nuclear Information System (INIS)

    Guo Yonghai; Dong Jiannan; Liu Shufen; Zhou Zhichao

    2014-01-01

    Aqishan area located in Xinjiang Uygur Automonous Region is one of the main preselected site of disposal repository for high-level radioactive waste (HLW) in our country. Groundwater chemical feature is one of the most important consideration factors in the siting and site evaluation for high-level radioactive waste repository, From 2012 to 2013, the regional field hydrogeochemical investigation was carried out in study area and more than 30 groundwater samples were collected. According to the measurement data, the groundwater chemical features for different subareas are discussed in the paper. Furthermore, the location of discharge area of groundwater in Aqishan area was estimated according to the chemical features of different subareas. (authors)

  19. NAMMU results for the regional groundwater flow in the Piceance Basin - HYDROCOIN Level 2-Test case 4

    International Nuclear Information System (INIS)

    Miller, D.R.; Paige, R.W.

    1988-07-01

    The HYDROCOIN project is an international collaborative venture for comparing groundwater flow models and modelling strategies. Level 2 of this project concerns the validation of models in order to test their ability adequately to represent reality. This report describes calculations for the regional groundwater flow in the Piceance Basin of northwestern Colorado. This region constitutes one of the few areas where low permeability rocks, similar to those likely to be used for repository sites, have been investigated by hydrogeologists. (author)

  20. Groundwater monitoring in the Savannah River Plant Low Level Waste Burial Ground

    Energy Technology Data Exchange (ETDEWEB)

    Carlton, W.H.

    1983-12-31

    This document describes chemical mechanisms that may affect trace-level radionuclide migration through acidic sandy clay soils in a humid environment, and summarizes the extensive chemical and radiochemical analyses of the groundwater directly below the SRP Low-Level Waste (LLW) Burial Ground (643-G). Anomalies were identified in the chemistry of individual wells which appear to be related to small amounts of fission product activity that have reached the water table. The chemical properties which were statistically related to trace level transport of Cs-137 and Sr-90 were iron, potassium, sodium and calcium. Concentrations on the order of 100 ppM appear sufficient to affect nuclide migration. Several complexation mechanisms for plutonium migration were investigated.

  1. Impact of groundwater levels on evaporation and water-vapor fluxes in highly saline soils

    Science.gov (United States)

    Munoz, J. F.; Hernández, M. F.; Braud, I.; Gironas, J. A.; Suarez, F. I.

    2012-12-01

    In aquifers of arid and hyper-arid zones, such as those occurring in the Chilean Andes high plateau, it is important to determine both the quantity and location of water discharges at the temporal scales of interest to close the basin's water budget and thus, to manage the water resource properly. In zones where shallow aquifers are the main source of water, overexploitation of the water resource changes the dynamics of water, heat and solute transport in the vadose zone. As aquifers are exploited, fluctuations in depth to groundwater are exacerbated. These fluctuations modify both soil structure and evaporation from the ground, which is typically the most important discharge from the water budget and is very difficult to estimate. Therefore, a correct quantification of evaporation from these soils is essential to improve the accuracy of the water balance estimation. The objective of this study was to investigate the evaporation processes and water-vapor fluxes in a soil column filled with a saline soil from the Salar del Huasco basin, Chile. Water content, electrical conductivity and temperature at different depths in the soil profile were monitored to determine the liquid and vapor fluxes within the soil column. The results showed that evaporation is negligible when the groundwater table is deeper than 1 m. For shallower groundwater levels, evaporation increases in an exponential fashion reaching a value of 3 mm/day when the groundwater table is near the surface of the ground. These evaporation rates are on the same order of magnitude than the field measurements, but slightly lower due to the controlled conditions maintained in the laboratory. Isothermal fluid fluxes were predominant over the non-isothermal fluid and water vapor fluxes. The net flux for all the phreatic levels tested in the laboratory showed different behaviors, with ascending or descending flows as a consequence of changes in water content and temperature distribution within the soil. It was

  2. Natural radioactivity levels in granitic plutons and groundwaters in Southeast part of Eskisehir, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Oerguen, Y. [Faculty of Mines, Istanbul Technical University (ITU), Ayazaga Kampusu, 34469 Istanbul (Turkey)]. E-mail: orgun@itu.edu.tr; Altinsoy, N. [Institute of Energy, Istanbul Technical University (ITU), Ayazaga Kampusu, 34469 Istanbul (Turkey); Gueltekin, A.H. [Faculty of Mines, Istanbul Technical University (ITU), Ayazaga Kampusu, 34469 Istanbul (Turkey); Karahan, G. [Cekmece Nuclear Research and Training Center, P.O. Box 1, Atatuerk Airport, 34149 Istanbul (Turkey); Celebi, N. [Cekmece Nuclear Research and Training Center, P.O. Box 1, Atatuerk Airport, 34149 Istanbul (Turkey)

    2005-08-01

    The present work investigated the radioactivity level of the granitoid plutons and its effect on the groundwaters in the southeast part of Eskisehir. Fourteen granitic samples from the Kaymaz and Sivrihisar plutons and 11 groundwater samples from the near vicinity of the pluton were analyzed. The activity concentrations measured for {sup 238}U and {sup 232}Th ranged from 43.59{+-}2 to 651.80{+-}24 Bq/kg, and 51.16{+-}3 to 351.94{+-}13 Bq/kg, respectively. The activity concentrations obtained for {sup 40}K varied from 418.50{+-}17 to 1618.03{+-}66 Bq/kg. The absorbed dose rates in air outdoors ranged from 87.14 to 531.81 nGy/h. All the results obtained from the Kaymaz pluton are higher than those from the Sivrihisar. The U (ave. 16.6 ppm) and Th (ave. 49.9 ppm) values of the Kaymaz pluton are higher than the average concentrations of the magmatic rocks of granitic composition. These results are consistent with high dose rates of the pluton. The gross-{alpha} activities in the groundwater samples ranged from 0.009 to 1.64 Bq/l and the gross-{beta} activities from 0.006 to 0.89 Bq/l. The highest gross-{alpha} value was found in the sample taken from near the Kaymaz pluton. The concentrations of {sup 222}Rn varied from 0.060 to 0.557 Bq/l.

  3. Microbial Community-Level Physiological Profiles (CLPP) and herbicide mineralization potential in groundwater affected by agricultural land use

    DEFF Research Database (Denmark)

    Janniche, Gry Sander; Spliid, Henrik; Albrechtsen, Hans-Jørgen

    2012-01-01

    Diffuse groundwater pollution from agricultural land use may impact the microbial groundwater community, which was investigated as Community-Level Physiological Profiles (CLPP) using EcoPlate™. Water was sampled from seven piezometers and a spring in a small agricultural catchment with diffuse......-galacturonic acid, tween 40, and 4-hydroxy benzoic acid as substrates, whereas none preferred 2-hydroxy benzoic acid, α-d-lactose, d,l-α-glycerol phosphate, α-ketobutyric acid, l-threonine and glycyl-l-glutamic acid. Principal Component Analysis of the CLPP's clustered the most agriculturally affected groundwater...... samples, indicating that the agricultural land use affects the groundwater microbial communities. Furthermore, the ability to mineralize atrazine and isoproturon, which have been used in the catchment, was also associated with this cluster....

  4. A natural analogy of high-level radioactive waste disposal. A case study of the groundwater from a uranium deposit

    International Nuclear Information System (INIS)

    Li Xinchun; Zhang Zhanshi; Ouyang Hegen

    2009-01-01

    Radionuclide migration is one of the key effects of high-level radioactive waste disposal. The groundwater is considered the primary means of radionuclide migration. Uranium and rare earth element(REE) in groundwater from a uranium deposit were used as a chemical analogue to study the migration of radionuclides. The results show that REE and its chemical analogue might migrate under the uranium deposit condition, but uranium and its analogue do not migrate obviously. According to the results, we might infer that after the groundwater penetrates into the HLW repository, REE and its analogue might migrate with the groundwater; but there is no obvious migration of uranium and its chemical analogue,which might increase our confidence to built a safe HLW repository. (authors)

  5. Predictive models applied to groundwater level forecasting: a preliminary experience on the alluvial aquifer of the Magra River (Italy).

    Science.gov (United States)

    Brozzo, Gianpiero; Doveri, Marco; Lelli, Matteo; Scozzari, Andrea

    2010-05-01

    Computer-based decision support systems are getting a growing interest for water managing authorities and water distribution companies. This work discusses a preliminary experience in the application of computational intelligence in a hydrological modeling framework, regarding the study area of the alluvial aquifer of the Magra River (Italy). Two sites in the studied area, corresponding to two distinct groups of wells (Battifollo and Fornola) are managed by the local drinkable water distribution company (ACAM Acque), which serves the area of La Spezia, on the Ligurian coast. Battifollo has 9 wells with a total extraction rate of about 240 liters per second, while Fornola has 44 wells with an extraction rate of about 900 liters per second. Objective of this work is to make use of time series coming from long-term monitoring activities in order to assess the trend of the groundwater level with respect to a set of environmental and exploitation parameters; this is accomplished by the experimentation of a suitable model, eligible to be used as a predictor. This activity moves on from the modeling of the system behavior, based on a set of Input/Output data, in order to characterize it without necessarily a prior knowledge of any deterministic mechanism (system identification). In this context, data series collected by continuous hydrological monitoring instrumentation installed in the studied sites, together with meteorological and water extraction data, have been analyzed in order to assess the applicability and performance of a predictive model of the groundwater level. A mixed approach (both data driven and process-based) has been experimented on the whole dataset relating to the last ten years of continuous monitoring activity. The system identification approach presented here is based on the integration of an adaptive technique based on Artificial Neural Networks (ANNs) and a blind deterministic identification approach. According to this concept, the behavior of

  6. Management of water resources to control groundwater levels in the southern area of the western Nile delta, Egypt

    Directory of Open Access Journals (Sweden)

    Mohamed M. Sobeih

    2017-10-01

    Full Text Available The present study was initiated with the objective of simulating and predicting the effect of future development on the groundwater flow and levels. This supports applications for future planning and wise management of water resources. The study area extends south of El Nubariya canal including Sadat City area and its vicinities in the western Nile delta region. A numerical groundwater flow model (MODFLOW has been employed to simulate flow and get the budget of groundwater in the study area. The model showed that about 28,101,041 m3/day of surface water is infiltrated to groundwater dominantly from canals and excess irrigation water. About the same quantity (28,101,052 m3/day, is discharged from groundwater through production wells, open drains and through some reaches of canals. Three development scenarios were simulated to give predictions of the impact of future increasing recharge, construction of new canal and new open drains, and also increased pumping on the groundwater levels in the study area.

  7. Nested-scale discharge and groundwater level monitoring to improve predictions of flow route discharges and nitrate loads

    Science.gov (United States)

    van der Velde, Y.; Rozemeijer, J. C.; de Rooij, G. H.; van Geer, F. C.; Torfs, P. J. J. F.; de Louw, P. G. B.

    2010-10-01

    Identifying effective measures to reduce nutrient loads of headwaters in lowland catchments requires a thorough understanding of flow routes of water and nutrients. In this paper we assess the value of nested-scale discharge and groundwater level measurements for predictions of catchment-scale discharge and nitrate loads. In order to relate field-site measurements to the catchment-scale an upscaling approach is introduced that assumes that scale differences in flow route fluxes originate from differences in the relationship between groundwater storage and the spatial structure of the groundwater table. This relationship is characterized by the Groundwater Depth Distribution (GDD) curve that relates spatial variation in groundwater depths to the average groundwater depth. The GDD-curve was measured for a single field site (0.009 km2) and simple process descriptions were applied to relate the groundwater levels to flow route discharges. This parsimonious model could accurately describe observed storage, tube drain discharge, overland flow and groundwater flow simultaneously with Nash-Sutcliff coefficients exceeding 0.8. A probabilistic Monte Carlo approach was applied to upscale field-site measurements to catchment scales by inferring scale-specific GDD-curves from hydrographs of two nested catchments (0.4 and 6.5 km2). The estimated contribution of tube drain effluent (a dominant source for nitrates) decreased with increasing scale from 76-79% at the field-site to 34-61% and 25-50% for both catchment scales. These results were validated by demonstrating that a model conditioned on nested-scale measurements simulates better nitrate loads and better predictions of extreme discharges during validation periods compared to a model that was conditioned on catchment discharge only.

  8. Groundwater levels and water quality during a 96-hour aquifer test in Pickaway County, Ohio, 2012

    Science.gov (United States)

    Haefner, Ralph J.; Runkle, Donna L.; Mailot, Brian E.

    2014-01-01

    During October–November 2012, a 96-hour aquifer test was performed at a proposed well field in northern Pickaway County, Ohio, to investigate groundwater with elevated nitrate concentrations. Earlier sampling done by the City of Columbus revealed that some wells had concentrations of nitrate that approached 10 milligrams per liter (mg/L), whereas other wells and the nearby Scioto River had concentrations from 2 to 6 mg/L. The purpose of the current test was to examine potential changes in water quality that may be expected if the site was developed into a public water-supply source; therefore, water-transmitting properties determined during a previous test were not determined a second time. Before and during the test, water-level data and water-quality samples were obtained from observation wells while a test production well was pumped at 1,300 gallons per minute. Before the test, local groundwater levels indicated that groundwater was being discharged to the nearby Scioto River, but during the test, the stream was losing streamflow owing to infiltration. Water levels declined in the pumping well, in adjacent observation wells, and in a nearby streambed piezometer as pumping commenced. The maximum drawdown in the pumping well was 29.75 feet, measured about 95 hours after pumping began. Water-quality data, including analyses for field parameters, major and trace elements, nutrients, and stable isotopes of oxygen and nitrogen in nitrate, demonstrated only small variations before and during the test. Concentrations of nitrate in five samples from the pumping well ranged from about 5.10 to 5.42 mg/L before and during the test, whereas concentrations of nitrate in five samples on or about the same sampling dates and times at a monitoring site on the Scioto River adjacent to the pumping well ranged from 3.46 to 4.97 mg/L. Water from two nearby observation wells had nitrate concentrations approaching 10 mg/L, which is the U.S. Environmental Protection Agency’s Maximum

  9. Comparative Influences of Precipitation and River Stage on Groundwater Levels in Near-River Areas

    Directory of Open Access Journals (Sweden)

    Incheol Kim

    2015-12-01

    Full Text Available The sustainable performance of foundations of various urban buildings and infrastructures is strongly affected by groundwater level (GWL, as GWL causes changes in the stress state within soil. In the present study, the components affecting GWL were investigated, focusing on the effects of precipitation and river stage. These components were analyzed using a six-year database established for hydrological and groundwater monitoring data. Five study regions for which daily measured precipitation, river stage, and GWL data were available were compared. Different periods of precipitation, geographical characteristics, and local surface conditions were considered in the analysis. The results indicated that key influence components on GWL are different depending on the hydrological, geological, and geographical characteristics of the target regions. River stage had the strongest influence on GWL in urban areas near large rivers with a high ratio of paved surface. In rural areas, where the paved surface area ratio and soil permeability were low, the moving average showed a closer correlation to GWL than river stage. A moving average-based method to predict GWL variation with time was proposed for regions with a low ratio of paved surface area and low permeability soils.

  10. A client-server software for the identification of groundwater vulnerability to pesticides at regional level.

    Science.gov (United States)

    Di Guardo, Andrea; Finizio, Antonio

    2015-10-15

    The groundwater VULnerability to PESticide software system (VULPES) is a user-friendly, GIS-based and client-server software developed to identify vulnerable areas to pesticides at regional level making use of pesticide fate models. It is a Decision Support System aimed to assist the public policy makers to investigate areas sensitive to specific substances and to propose limitations of use or mitigation measures. VULPES identify the so-called Uniform Geographical Unit (UGU) which are areas characterised by the same agro-environmental conditions. In each UGU it applies the PELMO model obtaining the 80th percentile of the substance concentration at 1 metre depth; then VULPES creates a vulnerability map in shapefile format which classifies the outputs comparing them with the lower threshold set to the legal limit concentration in groundwater (0.1 μg/l). This paper describes the software structure in details and a case study with the application of the terbuthylazine herbicide on the Lombardy region territory. Three zones with different degrees of vulnerabilities has been identified and described. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Using of pH as a tool to predict salinity of groundwater for irrigation purpose using artificial neural network

    Directory of Open Access Journals (Sweden)

    Mahmoud Nasr

    2014-01-01

    Full Text Available Monitoring of groundwater quality is one of the important tools to provide adequate information about water management. In the present study, artificial neural network (ANN with a feed-forward back-propagation was designed to predict groundwater salinity, expressed by total dissolved solids (TDS, using pH as an input parameter. Groundwater samples were collected from a 36 m depth well located in the experimental farm of the City of Scientific Researches and Technological Applications (SRTA City, New Borg El-Arab City, Alexandria, Egypt. The network structure was 1–5–3–1 and used the default Levenberg–Marquardt algorithm for training. It was observed that, the best validation performance, based on the mean square error, was 14819 at epoch 0, and no major problems or over-fitting occurred with the training step. The simulated output tracked the measured data with a correlation coefficient (R-value of 0.64, 0.67 and 0.90 for training, validation and test, respectively. In this case, the network response was acceptable, and simulation could be used for entering new inputs.

  12. Fracture network model of the groundwater flow in the Romuvaara site

    International Nuclear Information System (INIS)

    Poteri, A.; Laitinen, M.

    1997-01-01

    In the study, computer codes are employed to analyse the groundwater flow patterns in the sparcely fractured intact rock at the Romuvaara site. The new fracture data gathered during the detailed site characterisation phase demonstrated that the characteristic properties of fractures can be estimated quite reliably from few boreholes and outcrops. Results obtained by employing new methods, like the use of borehole-TV, changed the fracture intensity of the potential water conducting fractures compared to the earlier model. In the preliminary site investigation phase only the orientated fractures were used to derive the parameters of the intact rock. In the present model all the fractures outside the known fracture zones are used. The hydraulic conductivity tensor of the intact rock was estimated with the fracture network model. The flow simulations were calculated for a 16 x 16 x 16 m 3 rock volume and about 2000 fractures. The flow rate distribution through the cross sectional area of the disposal canisters was calculated for a set of ten realisations and a large number of different canister positions. The total number of canister positions simulated was 2200. The flow distribution in larger volume was studied using a method that searched the flow routes of highest conductance. The flow routes were examined into north-south, east-west and vertical directions. Flow routes along homogeneous and heterogeneous fractures were compared. (21 refs.)

  13. Value of information analysis for groundwater quality monitoring network design Case study: Eocene Aquifer, Palestine

    Science.gov (United States)

    Khader, A.; McKee, M.

    2010-12-01

    Value of information (VOI) analysis evaluates the benefit of collecting additional information to reduce or eliminate uncertainty in a specific decision-making context. It makes explicit any expected potential losses from errors in decision making due to uncertainty and identifies the “best” information collection strategy as one that leads to the greatest expected net benefit to the decision-maker. This study investigates the willingness to pay for groundwater quality monitoring in the Eocene Aquifer, Palestine, which is an unconfined aquifer located in the northern part of the West Bank. The aquifer is being used by 128,000 Palestinians to fulfill domestic and agricultural demands. The study takes into account the consequences of pollution and the options the decision maker might face. Since nitrate is the major pollutant in the aquifer, the consequences of nitrate pollution were analyzed, which mainly consists of the possibility of methemoglobinemia (blue baby syndrome). In this case, the value of monitoring was compared to the costs of treating for methemoglobinemia or the costs of other options like water treatment, using bottled water or importing water from outside the aquifer. And finally, an optimal monitoring network that takes into account the uncertainties in recharge (climate), aquifer properties (hydraulic conductivity), pollutant chemical reaction (decay factor), and the value of monitoring is designed by utilizing a sparse Bayesian modeling algorithm called a relevance vector machine.

  14. Screening-level risk assessment for styrene-acrylonitrile (SAN) trimer detected in soil and groundwater.

    Science.gov (United States)

    Kirman, C R; Gargas, M L; Collins, J J; Rowlands, J C

    2012-01-01

    A screening-level risk assessment was conducted for styrene-acrylonitrile (SAN) Trimer detected at the Reich Farm Superfund site in Toms River, NJ. Consistent with a screening-level approach, on-site and off-site exposure scenarios were evaluated using assumptions that are expected to overestimate actual exposures and hazards at the site. Environmental sampling data collected for soil and groundwater were used to estimate exposure point concentrations. Several exposure scenarios were evaluated to assess potential on-site and off-site exposures, using parameter values for exposures to soil (oral, inhalation of particulates, and dermal contact) and groundwater (oral, dermal contact) to reflect central tendency exposure (CTE) and reasonable maximum exposure (RME) conditions. Three reference dose (RfD) values were derived for SAN Trimer for short-term, subchronic, and chronic exposures, based upon its effects on the liver in exposed rats. Benchmark (BMD) methods were used to assess the relationship between exposure and response, and to characterize appropriate points of departure (POD) for each RfD. An uncertainty factor of 300 was applied to each POD to yield RfD values of 0.1, 0.04, and 0.03 mg/kg-d for short-term, subchronic, and chronic exposures, respectively. Because a chronic cancer bioassay for SAN Trimer in rats (NTP 2011a) does not provide evidence of carcinogenicity, a cancer risk assessment is not appropriate for this chemical. Potential health hazards to human health were assessed using a hazard index (HI) approach, which considers the ratio of exposure dose (i.e., average daily dose, mg/kg-d) to toxicity dose (RfD, mg/kg-d) for each scenario. All CTE and RME HI values are well below 1 (where the average daily dose is equivalent to the RfD), indicating that there is no concern for potential noncancer effects in exposed populations even under the conservative assumptions of this screening-level assessment.

  15. Determination of nitrogen reduction levels necessary to reach groundwater quality targets in Slovenia.

    Science.gov (United States)

    Andelov, Miso; Kunkel, Ralf; Uhan, Jože; Wendland, Frank

    2014-09-01

    Within a collaborative project between Slovenian Environment Agency (ARSO) and Research Center Jülich (FZJ), nitrogen reduction levels necessary to reach groundwater quality targets in Slovenia were assessed. For this purpose the hydrological model GROWA-DENUZ was coupled with agricultural N balances and applied consistently to the whole territory of Slovenia in a spatial resolution of 100×100m. GROWA was used to determine the water balance in Slovenia for the hydrologic period 1971-2000. Simultaneously, the displaceable N load in soil was assessed from agricultural Slovenian N surpluses for 2011 and the atmospheric N deposition. Subsequently, the DENUZ model was used to assess the nitrate degradation in soil and, in combination with the percolation water rates from the GROWA model, to determine nitrate concentration in the leachate. The areas showing predicted nitrate concentrations in the leachate above the EU groundwater quality standard of 50mg NO3(-)/L have been identified as priority areas for implementing nitrogen reduction measures. For these "hot spot" areas DENUZ was used in a backward mode to quantify the maximal permissible nitrogen surplus levels in agriculture to guarantee a nitrate concentration in percolation water below 50mg NO3(-)/L. Model results indicate that additional N reduction measures should be implemented in priority areas rather than area-covering. Research work will directly support the implementation of the European Union Water Framework Directive in Slovenia, e.g., by using the maximal permissible nitrogen surplus levels as a framework for the derivation of regionally adapted and hence effective nitrogen reduction measures. Copyright © 2014. Published by Elsevier B.V.

  16. Levels, Linkages, and Networks in Cross-Cultural Innovation.

    Science.gov (United States)

    Kennedy, Judith; Kennedy, Chris

    1998-01-01

    Individuals belong to different cultural networks, and these networks and connections between them play an important role in success or failure of educational innovation and should be included in any model of the management or evaluation of innovation. Looks at functions of the different networks to which individuals belong at three levels,…

  17. A practical algorithm for reconstructing level-1 phylogenetic networks

    NARCIS (Netherlands)

    Huber, K.T.; Iersel, van L.J.J.; Kelk, S.M.; Suchecki, R.

    2011-01-01

    Recently, much attention has been devoted to the construction of phylogenetic networks which generalize phylogenetic trees in order to accommodate complex evolutionary processes. Here, we present an efficient, practical algorithm for reconstructing level-1 phylogenetic networks-a type of network

  18. Seismic effects on bedrock and underground constructions. A literature survey of damage on constructions; Changes in groundwater levels and flow; Changes in chemistry in groundwater and gases

    International Nuclear Information System (INIS)

    Roeshoff, Kennert.

    1989-06-01

    This report is a literature review of direct and indirect effects of earthquakes on underground constructions as tunnels, caverns and mines. The direct damage will cause vibrations, shaking and displacement, which may lead to partial or total destruction of the underground facility. Damage caused by shaking has been reported in several studies, and several hundreds of events have been reported both from mines and tunnels. These reports are mainly from active earthquake areas. There are very few reports of damage caused by displacements on an existing fault. The damage, which may be severe, is generally concentrated to the vicinity of the fault zone. The report also includes a review of the effects caused by earthquakes on groundwater level, flow, pressure, chemistry and constituents in the ground. Such changes are mainly reported from studies in wells near active faults. The interesting coupling of changes in groundwater characteristics around an underground construction is, unfortunately, very seldom reported. The groundwater level and pressure changes are discussed in Chapter 4. The bases for this part of the review is taken from the Alaska earthquake 1964. Other observations are reported from wells and reservoirs located near existing faults. Changes of the geochemistry in groundwater and soil gases are reviewed in Chapter 4. The mechanisms of seismochemical anomalies are discussed and examples of short and long term monitoring are given from USA, Soviet Union and China. Gases in ground water and soil is reported in Chapter 5. Radon is so far one of the most studied species and its variation in short, medium and long term with seismic activity is rather well understood. Other gases or isotopes that have been studied include helium, carbon dioxide, hydrogen, argon and methane, radium and uranium. The paper also includes same statements for repository design based on the result of the review. (81 refs.)

  19. Simulating groundwater-induced sewer flooding

    Science.gov (United States)

    Mijic, A.; Mansour, M.; Stanic, M.; Jackson, C. R.

    2016-12-01

    During the last decade, Chalk catchments of southern England experienced severe groundwater flooding. High groundwater levels resulted in the groundwater ingress into the sewer network that led to restricted toilet use and the overflow of diluted, but untreated sewage to road surfaces, rivers and water courses. In response to these events the water and sewerage company Thames Water Utilities Ltd (TWUL) had to allocate significant funds to mitigate the impacts. It was estimated that approximately £19m was spent responding to the extreme wet weather of 2013-14, along with the use of a fleet of over 100 tankers. However, the magnitude of the event was so large that these efforts could not stop the discharge of sewage to the environment. This work presents the analysis of the risk of groundwater-induced sewer flooding within the Chalk catchment of the River Lambourn, Berkshire. A spatially distributed groundwater model was used to assess historic groundwater flood risk and the potential impacts of changes in future climate. We then linked this model to an urban groundwater model to enable us to simulate groundwater-sewer interaction in detail. The modelling setup was used to identify relationships between infiltration into sewers and groundwater levels at specific points on TWUL's sewer network, and to estimate historic and future groundwater flood risk, and how this varies across the catchment. The study showed the significance of understanding the impact of groundwater on the urban water systems, and producing information that can inform a water company's response to groundwater flood risk, their decision making process and their asset management planning. However, the knowledge gained through integrated modelling of groundwater-sewer interactions has highlighted limitations of existing approaches for the simulation of these coupled systems. We conclude this work with number of recommendations about how to improve such hydrological/sewer analysis.

  20. Uncertainty characteristics of EPA's ground-water transport model for low-level waste performance assessment

    International Nuclear Information System (INIS)

    Yim, Man-Sung

    1995-01-01

    Performance assessment is an essential step either in design or in licensing processes to ensure the safety of any proposed radioactive waste disposal facilities. Since performance assessment requires the use of computer codes, understanding the characteristics of computer models used and the uncertainties of the estimated results is important. The PRESTO-EPA code, which was the basis of the Environmental Protection Agency's analysis for low-level-waste rulemaking, is widely used for various performance assessment activities in the country with no adequate information available for the uncertainty characteristics of the results. In this study, the groundwater transport model PRESTO-EPA was examined based on the analysis of 14 C transport along with the investigation of uncertainty characteristics

  1. Ground-water development and the effects on ground-water levels and water quality in the town of Atherton, San Mateo County, California

    Science.gov (United States)

    Metzger, Loren F.; Fio, John L.

    1997-01-01

    The installation of at least 100 residential wells in the town of Atherton, California, during the 198792 drought has raised concerns about the increased potential for land subsidence and salt water intrusion. Data were collected and monitor ing networks were established to assess current processes and to monitor future conditions affect ing these processes. Data include recorded pump age, recorded operation time, and measured pumpage rates from 38 wells; water levels from 49 wells; water chemistry samples from 20 wells, and land-surface elevation data from 22 survey sites, including one National Geodetic Survey estab lished bench mark. Geologic, lithologic, climato logic, well construction, well location, and historical information obtained from available reports and local, state, and Federal agencies were used in this assessment. Estimates of annual residential pumpage from 269 assumed active residential wells in the study area indicate that the average annual total pumping rate is between 395 and 570 acre-feet per year. The nine assumed active institutional wells are estimated to pump a total of about 200 acre- feet per year, or 35 to 50 percent of the total resi dential pumpage. Assuming that 510 acre-feet per year is the best estimate of annual residential pumpage, total pumpage of 710 acre-feet per year would represent about 19 percent of the study area's total water supply, as estimated. Depth-to-water-level measurements in wells during April 1993 through September 1995 typically ranged from less than 20 feet below land surface nearest to San Francisco Bay to more than 70 feet below land surface in upslope areas near exposed bedrock, depending on the season. This range, which is relatively high historically, is attributed to above normal rainfall between 1993 and 1995. Water levels expressed as hydraulic heads indicate the presence of three different hydrologic subareas on the basis of hydraulic-head contour configurations and flow direction. That all

  2. Fluctuations in groundwater levels related to regional and local withdrawals in the fractured-bedrock groundwater system in northern Wake County, North Carolina, March 2008-February 2009

    Science.gov (United States)

    Chapman, Melinda J.; Almanaseer, Naser; McClenney, Bryce; Hinton, Natalie

    2011-01-01

    A study of dewatering of the fractured-bedrock aquifer in a localized area of east-central North Carolina was conducted from March 2008 through February 2009 to gain an understanding of why some privately owned wells and monitoring wells were intermittently dry. Although the study itself was localized in nature, the resulting water-resources data and information produced from the study will help enable resource managers to make sound water-supply and water-use decisions in similar crystalline-rock aquifer setting in parts of the Piedmont and Blue Ridge Physiographic Provinces. In June 2005, homeowners in a subdivision of approximately 11 homes on lots approximately 1 to 2 acres in size in an unincorporated area of Wake County, North Carolina, reported extremely low water pressure and temporarily dry wells during a brief period. This area of the State, which is in the Piedmont Physiographic Province, is undergoing rapid growth and development. Similar well conditions were reported again in July 2007. In an effort to evaluate aquifer conditions in the area of intermittent water loss, a study was begun in March 2008 to measure and monitor water levels and groundwater use. During the study period from March 2008 through February 2009, regular dewatering of the fractured-bedrock aquifer was documented with water levels in many wells ranging between 100 and 200 feet below land surface. Prior to this period, water levels from the 1980s through the late 1990s were reported to range from 15 to 50 feet below land surface. The study area includes three community wells and more than 30 private wells within a 2,000-foot radius of the dewatered private wells. Although groundwater levels were low, recovery was observed during periods of heavy rainfall, most likely a result of decreased withdrawals owing to less demand for irrigation purposes. Similar areal patterns of low groundwater levels were delineated during nine water-level measurement periods from March 2008 through

  3. Quantification of uranium levels in groundwater in the municipality of San Diego de la Union Mexico

    International Nuclear Information System (INIS)

    Hernandez M, H.; Rios L, M. J.; Gaytan H, D.; Romero G, E. T.

    2017-10-01

    The objective of this work was to quantify the levels of uranium (U) in groundwater from 22 wells in the municipality of San Diego de la Union Mexico. The sampled wells were classified as not regularized and regularized according to records of the National Water Commission and classified by zones A, B, C, D and E. Samples were collected in triplicate in 1 L bottles, then acidified with ultra pure HNO 3 at 2% v/v and conserved at 4 degrees Celsius until analysis by mass spectrometry with magnetic sector with inductively coupled plasma source (Icp-SFMS). The preparation method was the acid digestion in the open system and re-concentration of the sample. In addition, 1 μg L -1 of indium (In) was used as a tracer to know the performance of the method. Finally, the samples were diluted in 10 ml and introduced to the Icp-SFMS to measure in low resolution the U isotopes (U-234, U-235 and U-238). The average results obtained from total U were: A= 3.65 ± 1.89 μg L -1 , B= 6.37 ± 1.46 μg L -1 , C= 3.20 ± 2.27 μg L -1 , D= 3.87 ± 1.31 μg L -1 and E= 4.44 ± 1.17 μg L -1 . According to the official Mexican standard NOM-014-CONAGUA-2003, the U levels found in the groundwater of San Diego de la Union Mexico do not exceed the permissible limits of 30 μg/L. (Author)

  4. Groundwater-level and storage-volume changes in the Equus Beds aquifer near Wichita, Kansas, predevelopment through January 2015

    Science.gov (United States)

    Whisnant, Joshua A.; Hansen, Cristi V.; Eslick, Patrick J.

    2015-10-01

    Development of the Wichita well field began in the 1940s in the Equus Beds aquifer to provide the city of Wichita, Kansas, a new water-supply source. After development of the Wichita well field began, groundwater levels began to decline. Extensive development of irrigation wells that began in the 1970s also contributed to substantial groundwater-level declines. Groundwater-level declines likely enhance movement of brine from past oil and gas production near Burrton, Kansas, and natural saline water from the Arkansas River into the Wichita well field. Groundwater levels reached a historical minimum in 1993 because of drought conditions, irrigation, and the city of Wichita’s withdrawals from the aquifer. In 1993, the city of Wichita adopted the Integrated Local Water Supply Program to ensure that Wichita’s water needs would be met through the year 2050 and beyond as part of its efforts to manage the part of the Equus Beds aquifer Wichita uses. A key component of the Integrated Local Water Supply Program was the Equus Beds Aquifer Storage and Recovery project. The Aquifer Storage and Recovery project’s goal is to store and eventually recover groundwater and help protect the Equus Beds aquifer from oil-field brine water near Burrton, Kansas, and saline water from the Arkansas River. Since 1940, the U.S. Geological Survey has monitored groundwater levels and storage-volume changes in the Equus Beds aquifer to provide data to the city of Wichita in order to better manage its water supply.

  5. Prediction of contamination potential of groundwater arsenic in Cambodia, Laos, and Thailand using artificial neural network

    Science.gov (United States)

    The arsenic (As) contamination of groundwater has increasingly been recognized as a major global issue of concern. As groundwater resources are one of most important freshwater sources for water supplies in Southeast Asian countries, it is important to investigate the spatial distribution of As cont...

  6. Effects of groundwater levels and headwater wetlands on streamflow in the Charlie Creek basin, Peace River watershed, west-central Florida

    Science.gov (United States)

    Lee, T.M.; Sacks, L.A.; Hughes, J.D.

    2010-01-01

    storage, rainfall-runoff processes, and groundwater-level differences in the upper basin allow it to generate approximately half of the streamflow from the Charlie Creek basin. Therefore, future development in the upper basin that would alter the hydraulic connectivity of wetlands during high flow conditions or expand recharging groundwater conditions could substantially affect streamflow in Charlie Creek. LIDAR (Light detection and ranging) based topographic maps and integrated modeling results were used to quantify the water stored in wetlands and other topographic depressions, and to describe the network of shallow stream channels connecting wetlands to Charlie Creek and its tributaries over distances of several thousand feet. Peak flows at all but one streamflow station were underpredicted in MIKE SHE simulations, possibly because the hydraulics of surface channels connecting wetlands to stream channels were not explicitly simulated in the model. Explicitly simulating the smaller channels connecting wetlands and stream channels should improve the ability of future watershed models to simulate peak flows in streams with headwater wetlands. The runoff potential was greater in the lower half of the Charlie Creek basin than in the upper half, and the streambed of Charlie Creek had greater potential to both directly gain streamflow from groundwater and lose streamflow to groundwater. Charlie Creek is more incised into the surficial aquifer in the lower basin than in the upper basin, and the streambed intersects the top of the intermediate aquifer system at two known locations. Groundwater levels in the intermediate aquifer system varied widely in the lower half of the basin from artesian conditions inducing upward flow toward the surficial aquifer and streams, to recharging conditions allowing downward flow and stream leakage. Recharge areas were greatest in May 2004 when rainfall was at a seasonal low and irrigation pumping was at a seasonal high. Recharge conditions

  7. Determination of polycyclic aromatic hydrocarbon levels of groundwater in Ife north local government area of Osun state, Nigeria

    Directory of Open Access Journals (Sweden)

    Abolanle Saheed Adekunle

    Full Text Available This study determined the presence and levels of Polycyclic Aromatic Hydrocarbons (PAHs of groundwater in Moro, Edun-Abon, Yakoyo and Ipetumodu communities in Ife-North Local Government Area of Osun State. This was with a view to create public awareness about the safety of groundwater as a source for domestic purposes (e.g., drinking, cooking etc. in non-industrial area. Water samples were collected on seasonal basis, comprising of three months (August–October in the wet season and three months (December–February in the dry season. The PAHs in the water samples were extracted with n-hexane using liquid–liquid extraction method, while their qualitative identifications and quantitative estimations were carried out with the use of gas chromatography. Levels of PAHs detected showed predominance of light PAHs (less than four fused rings for both wet and the dry seasons. Higher concentrations of PAHs were recorded during the wet season than the dry season. The study concluded that the groundwater in the communities was contaminated with light PAHs and the total PAHs in this area exceeded the maximum permissible limit of 10 μg L−1 recommended by World Health Organization (WHO for safety of groundwater. Keywords: Polycyclic aromatic hydrocarbons, Groundwater, Water quality, Seasonal variation, Health impact

  8. Incorporation of groundwater losses and well level data in rainfall-runoff models illustrated using the PDM

    Directory of Open Access Journals (Sweden)

    R. J. Moore

    2002-01-01

    Full Text Available Intermittent streamflow is a common occurrence in permeable catchments, especially where there are pumped abstractions to water supply. Many rainfall-runoff models are not formulated so as to represent ephemeral streamflow behaviour or to allow for the possibility of negative recharge arising from groundwater pumping. A groundwater model component is formulated here for use in extending existing rainfall-runoff models to accommodate such ephemeral behaviour. Solutions to the Horton-Izzard equation resulting from the conceptual model of groundwater storage are adapted and the form of nonlinear storage extended to accommodate negative inputs, water storage below which outflow ceases, and losses to external springs and underflows below the gauged catchment outlet. The groundwater model component is demonstrated through using it as an extension of the PDM rainfall-runoff model. It is applied to the River Lavant, a catchment in Southern England on the English Chalk, where it successfully simulates the ephemeral streamflow behaviour and flood response together with well level variations. Keywords: groundwater, rainfall-runoff model, ephemeral stream, well level, spring, abstraction

  9. A simplified model for assessing the impact to groundwater of swine farms at regional level

    Science.gov (United States)

    Massabo, Marco; Viterbo, Angelo

    2013-04-01

    Swine manure can be an excellent source of nutrients for crop production. Several swine farms are present in the territory of Regione Umbria and more than 200.000 of swine heads are present yearly in the whole territory while some municipalities host more than 30.000 heads over a relatively limited land. Municipality with elevated number of swine heads has registered particularly higher Nitrate concentration in groundwater that requires a management plan and intervention in order to determine the maximum allowed N loads in the specific region. Use of manure and fertilizers in agricultural field produce diffuse nitrogen (N) losses that are a major cause of excessive nitrate concentrations in ground and surface waters and have been of concern since decades. Excessive nitrate concentrations in groundwater can have toxic effects when used as drinking water and cause eutrophication in surface waters. For management and environmental planning purposes, it is necessary to assess the magnitude of diffuse N losses from agricultural fields and how they are influenced by factors such as management practices, type of fertilizers -organic or inorganic - climate and soil etc. There are several methods for assessing N leaching, they span from methods based on field test to complex models that require many input data. We use a simple index method that accounts for the type of fertilizer used - inorganic, swine or cattle manure- and hydrological and hydrogeological conditions. Hydrological conditions such as infiltration rates are estimated by a fully distributed hydrological model. Data on inorganic and organic fertilization are estimated at municipal level by using the nutrient crops needs and the statistics of swine and cattle heads within the municipality. The index method has been calibrated by using groundwater concentration as a proxy of N losses from agriculture. A time series of three years of data has been analyzed. The application of the simple index method allowed to

  10. A decision tree model to estimate the value of information provided by a groundwater quality monitoring network

    Science.gov (United States)

    Khader, A. I.; Rosenberg, D. E.; McKee, M.

    2013-05-01

    Groundwater contaminated with nitrate poses a serious health risk to infants when this contaminated water is used for culinary purposes. To avoid this health risk, people need to know whether their culinary water is contaminated or not. Therefore, there is a need to design an effective groundwater monitoring network, acquire information on groundwater conditions, and use acquired information to inform management options. These actions require time, money, and effort. This paper presents a method to estimate the value of information (VOI) provided by a groundwater quality monitoring network located in an aquifer whose water poses a spatially heterogeneous and uncertain health risk. A decision tree model describes the structure of the decision alternatives facing the decision-maker and the expected outcomes from these alternatives. The alternatives include (i) ignore the health risk of nitrate-contaminated water, (ii) switch to alternative water sources such as bottled water, or (iii) implement a previously designed groundwater quality monitoring network that takes into account uncertainties in aquifer properties, contaminant transport processes, and climate (Khader, 2012). The VOI is estimated as the difference between the expected costs of implementing the monitoring network and the lowest-cost uninformed alternative. We illustrate the method for the Eocene Aquifer, West Bank, Palestine, where methemoglobinemia (blue baby syndrome) is the main health problem associated with the principal contaminant nitrate. The expected cost of each alternative is estimated as the weighted sum of the costs and probabilities (likelihoods) associated with the uncertain outcomes resulting from the alternative. Uncertain outcomes include actual nitrate concentrations in the aquifer, concentrations reported by the monitoring system, whether people abide by manager recommendations to use/not use aquifer water, and whether people get sick from drinking contaminated water. Outcome costs

  11. Evaluation of natural attenuation processes in the groundwater of a tar oil contaminated site: development of a monitoring network

    International Nuclear Information System (INIS)

    Borke, P.; Husers, N.; Werner, P.; Leibenath, C.

    2005-01-01

    Tar oil is a complex mixture of mainly aromatic hydrocarbons. It is found in the subsurface of manufactured gas plants (MGP), coking plants or wood preserving facilities. The transportation into the soil and groundwater stands for a severe contamination. This is due to the physico-chemical properties of the DNAPL (dense non aqueous phase liquid) and its mobility in the soil and aquifer system. Additionally most of the contaminants show a low biological degradability and solubility under in situ conditions. Therefore it is known as a long term source of contamination. Nevertheless, natural attenuation (NA) processes are detectable at tar oil contaminated sites. In the thematic network two of the German funding priority KORA (http://www.natural-attenuation.de) these processes are matter of investigation. Four typical contaminated sites were chosen to evaluate under which circumstances monitored natural attenuation (MNA) is applicable. Furthermore enhanced natural attenuation questions are examined. The design of monitoring networks at tar oil contaminated sites plays a significant role in gaining field evidence for natural attenuation as well as documenting the efficiency of the attenuation processes and evaluating the matching of performance goals. Well designed monitoring networks include the placement of monitoring wells in 3D so that 3D flow path, mass balances and an estimation of mass flux can be monitored. As an example the history of the monitoring network of a wood preserving facility is shown. Starting from a risk assessment network to a network for MNA is presented. In this case for example especially the determination of the groundwater flow direction in time and space is connected to the number of observation wells and their location. Moreover in the beginning the observation wells were located according to the assumed centerline of the plume. Because of the variability of the groundwater flow direction and the need to determine mass flux a control plane

  12. Research on the contamination levels of norovirus in food facilities using groundwater in South Korea, 2015-2016.

    Science.gov (United States)

    Lee, Jeong Su; Joo, In Sun; Ju, Si Yeon; Jeong, Min Hee; Song, Yun-Hee; Kwak, Hyo Sun

    2018-09-02

    Norovirus (NoV) is a major pathogenic virus that is responsible for foodborne and waterborne gastroenteritis outbreaks. Groundwater is an important source of drinking water and is used in agriculture and food manufacturing processes. This study investigated norovirus contamination of groundwater treatment systems at 1360 sites in seven metropolitan areas and nine provinces in 2015-2016. Temperature, pH, residual chlorine, and turbidity content were assessed to analyze the water quality. In 2015, six sites were positive for the presence of NoV (0.88%) and in 2016, two sites were positive (0.29%); in total, NoV was detected in 8 of the 1360 sample sites (0.59%) investigated. Identified genotypes of NoV in groundwater included GI.5, 9 and GII.4, 6, 13, 17, and 21. GII.17 was the most prevalent genotype in treated groundwater used in the food industry. This dominance of GII.17 was corroborated by NoV infection outbreak cases and the results of a survey of coastal waters in South Korea in 2014-2015. Although a low detection rate was observed in this study, NoV is a pathogen that can spread extensively. Therefore, it is necessary to periodically monitor levels of norovirus which is responsible for food poisoning in groundwater. This is a first report to reveal epidemic genotype shift of norovirus in groundwater treatment system of food facilities in South Korea. Our results may contribute to the enhancement of public health and sanitary conditions by providing molecular epidemiological information on groundwater NoV. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Neural Network approach to assess the thermal affected zone around the injection well in a groundwater heat pump system

    Science.gov (United States)

    Lo Russo, Stefano; Taddia, Glenda; Verda, Vittorio

    2014-05-01

    The common use of well doublets for groundwater-sourced heating or cooling results in a thermal plume of colder or warmer re-injected groundwater known as the Thermal Affected Zone(TAZ). The plumes may be regarded either as a potential anthropogenic geothermal resource or as pollution, depending on downstream aquifer usage. A fundamental aspect in groundwater heat pump (GWHP) plant design is the correct evaluation of the thermally affected zone that develops around the injection well. Temperature anomalies are detected through numerical methods. Crucial elements in the process of thermal impact assessment are the sizes of installations, their position, the heating/cooling load of the building, and the temperature drop/increase imposed on the re-injected water flow. For multiple-well schemes, heterogeneous aquifers, or variable heating and cooling loads, numerical models that simulate groundwater and heat transport are needed. These tools should consider numerous scenarios obtained considering different heating/cooling loads, positions, and operating modes. Computational fluid dynamic (CFD) models are widely used in this field because they offer the opportunity to calculate the time evolution of the thermal plume produced by a heat pump, depending on the characteristics of the subsurface and the heat pump. Nevertheless, these models require large computational efforts, and therefore their use may be limited to a reasonable number of scenarios. Neural networks could represent an alternative to CFD for assessing the TAZ under different scenarios referring to a specific site. The use of neural networks is proposed to determine the time evolution of the groundwater temperature downstream of an installation as a function of the possible utilization profiles of the heat pump. The main advantage of neural network modeling is the possibility of evaluating a large number of scenarios in a very short time, which is very useful for the preliminary analysis of future multiple

  14. Isotope method for the recognition of groundwater formation in China's preselected high level radioactive waste disposal repository site

    International Nuclear Information System (INIS)

    Guo Yonghai; Wang Ju; Liu Shufen; Su Rui; Lu Chuanhe

    2005-01-01

    Yemaquan region in Beishan area. Gansu province, is one of the preselected sites of disposal repository for high level radioactive waste (HLW) in our country. Hydrogeological condition is an important aspect for site evaluation and the groundwater formation is a key factor to reflect the hydrogeological conditions for a certain area. Isotopic method is the one of the important means to determine the groundwater formation. Through the sampling and analysis of shallow groundwater isotopes of Yemaquan region, combined with geological, hydrogeological and hydrogeochemical characteristics, the issue of groundwater formation in the study region was discussed. The main cognition is that the groundwater in the region was formed from the infiltration of modern rainfall and the strong evaporation was happened for the shallow groundwater, which indicates the circulation conditions were relatively good for the shallow groundwater. This cognition provides very important hydrogeological information and basis for the evaluation of Yemaquan preselected site. (authors)

  15. Numerical simulation of groundwater flow in LILW Repository site:I. Groundwater flow modeling

    Energy Technology Data Exchange (ETDEWEB)

    Park, Koung Woo; Ji, Sung Hoon; Kim, Chun Soo; Kim, Kyoung Su [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Ji Yeon [Korea Hydro and Nuclear Power Co. Ltd., Seoul (Korea, Republic of)

    2008-12-15

    Based on the site characterization works in a low and intermediate level waste (LILW) repository site, the numerical simulations for groundwater flow were carried out in order to understand the groundwater flow system of repository site. To accomplish the groundwater flow modeling in the repository site, the discrete fracture network (DFN) model was constructed using the characteristics of fracture zones and background fractures. At result, the total 10 different hydraulic conductivity(K) fields were obtained from DFN model stochastically and K distributions of constructed mesh were inputted into the 10 cases of groundwater flow simulations in FEFLOW. From the total 10 numerical simulation results, the simulated groundwater levels were strongly governed by topography and the groundwater fluxes were governed by locally existed high permeable fracture zones in repository depth. Especially, the groundwater table was predicted to have several tens meters below the groundwater table compared with the undisturbed condition around disposal silo after construction of underground facilities. After closure of disposal facilities, the groundwater level would be almost recovered within 1 year and have a tendency to keep a steady state of groundwater level in 2 year.

  16. Nonradiological groundwater quality at low-level radioactive waste disposal sites

    International Nuclear Information System (INIS)

    Goode, D.J.

    1986-04-01

    The NRC is investigating appropriate regulatory options for disposal of low-level radioactive waste containing nonradiological hazardous constituents, as defined by EPA regulations. Standard EPA/RCRA procedures to determine hazardous organics, metals, indicator parameters, and general water quality are applied to samples from groundwater monitoring wells at two commercial low-level radioactive waste disposal sites. At the Sheffield, IL site (nonoperating), several typical organic solvents are identified in elevated concentrations in onsite wells and in an offsite area exhibiting elevated tritium concentrations. At the Barnwell, SC site (operating), only very low concentrations of three organics are found in wells adjacent to disposal units. Hydrocarbons associated with petroleum products are detected at both sites. Hazardous constituents associated with previosuly identified major LLW mixed waste streams, toluene, xylene, chromium, and lead, are at or below detection limits or at background levels in all samples. Review of previously collected data also supports the conclusion that organic solvents are the primary nonradiological contaminants associated with LLW disposal

  17. A Study of the Groundwater Level Spatial Variability in the Messara Valley of Crete

    Science.gov (United States)

    Varouchakis, E. A.; Hristopulos, D. T.; Karatzas, G. P.

    2009-04-01

    The island of Crete (Greece) has a dry sub-humid climate and marginal groundwater resources, which are extensively used for agricultural activities and human consumption. The Messara valley is located in the south of the Heraklion prefecture, it covers an area of 398 km2, and it is the largest and most productive valley of the island. Over-exploitation during the past thirty (30) years has led to a dramatic decrease of thirty five (35) meters in the groundwater level. Possible future climatic changes in the Mediterranean region, potential desertification, population increase, and extensive agricultural activity generate concern over the sustainability of the water resources of the area. The accurate estimation of the water table depth is important for an integrated groundwater resource management plan. This study focuses on the Mires basin of the Messara valley for reasons of hydro-geological data availability and geological homogeneity. The research goal is to model and map the spatial variability of the basin's groundwater level accurately. The data used in this study consist of seventy (70) piezometric head measurements for the hydrological year 2001-2002. These are unevenly distributed and mostly concentrated along a temporary river that crosses the basin. The range of piezometric heads varies from an extreme low value of 9.4 meters above sea level (masl) to 62 masl, for the wet period of the year (October to April). An initial goal of the study is to develop spatial models for the accurate generation of static maps of groundwater level. At a second stage, these maps should extend the models to dynamic (space-time) situations for the prediction of future water levels. Preliminary data analysis shows that the piezometric head variations are not normally distributed. Several methods including Box-Cox transformation and a modified version of it, transgaussian Kriging, and Gaussian anamorphosis have been used to obtain a spatial model for the piezometric head. A

  18. Predicting arsenic concentrations in groundwater of San Luis Valley, Colorado: implications for individual-level lifetime exposure assessment.

    Science.gov (United States)

    James, Katherine A; Meliker, Jaymie R; Buttenfield, Barbara E; Byers, Tim; Zerbe, Gary O; Hokanson, John E; Marshall, Julie A

    2014-08-01

    Consumption of inorganic arsenic in drinking water at high levels has been associated with chronic diseases. Risk is less clear at lower levels of arsenic, in part due to difficulties in estimating exposure. Herein we characterize spatial and temporal variability of arsenic concentrations and develop models for predicting aquifer arsenic concentrations in the San Luis Valley, Colorado, an area of moderately elevated arsenic in groundwater. This study included historical water samples with total arsenic concentrations from 595 unique well locations. A longitudinal analysis established temporal stability in arsenic levels in individual wells. The mean arsenic levels for a random sample of 535 wells were incorporated into five kriging models to predict groundwater arsenic concentrations at any point in time. A separate validation dataset (n = 60 wells) was used to identify the model with strongest predictability. Findings indicate that arsenic concentrations are temporally stable (r = 0.88; 95 % CI 0.83-0.92 for samples collected from the same well 15-25 years apart) and the spatial model created using ordinary kriging best predicted arsenic concentrations (ρ = 0.72 between predicted and observed validation data). These findings illustrate the value of geostatistical modeling of arsenic and suggest the San Luis Valley is a good region for conducting epidemiologic studies of groundwater metals because of the ability to accurately predict variation in groundwater arsenic concentrations.

  19. Topographic controls on shallow groundwater levels in a steep, prealpine catchment: When are the TWI assumptions valid?

    NARCIS (Netherlands)

    Rinderer, M.; van Meerveld, H.J.; Seibert, J.

    2014-01-01

    Topographic indices like the Topographic Wetness Index (TWI) have been used to predict spatial patterns of average groundwater levels and to model the dynamics of the saturated zone during events (e.g., TOPMODEL). However, the assumptions underlying the use of the TWI in hydrological models, of

  20. The backend design of an environmental monitoring system upon real-time prediction of groundwater level fluctuation under the hillslope.

    Science.gov (United States)

    Lin, Hsueh-Chun; Hong, Yao-Ming; Kan, Yao-Chiang

    2012-01-01

    The groundwater level represents a critical factor to evaluate hillside landslides. A monitoring system upon the real-time prediction platform with online analytical functions is important to forecast the groundwater level due to instantaneously monitored data when the heavy precipitation raises the groundwater level under the hillslope and causes instability. This study is to design the backend of an environmental monitoring system with efficient algorithms for machine learning and knowledge bank for the groundwater level fluctuation prediction. A Web-based platform upon the model-view controller-based architecture is established with technology of Web services and engineering data warehouse to support online analytical process and feedback risk assessment parameters for real-time prediction. The proposed system incorporates models of hydrological computation, machine learning, Web services, and online prediction to satisfy varieties of risk assessment requirements and approaches of hazard prevention. The rainfall data monitored from the potential landslide area at Lu-Shan, Nantou and Li-Shan, Taichung, in Taiwan, are applied to examine the system design.

  1. Nested-scale discharge and groundwater level monitoring to improve predictions of flow route discharges and nitrate loads

    NARCIS (Netherlands)

    Velde, Y. van der; Rozemeijer, J.C.; Rooij, G.H.de; Geer, F.C. van; Torfs, P.J.J.F.; Louw, P.G.B. de

    2010-01-01

    Identifying effective measures to reduce nutrient loads of headwaters in lowland catchments requires a thorough understanding of flow routes of water and nutrients. In this paper we assess the value of nested-scale discharge and groundwater level measurements for predictions of catchment-scale

  2. [Effects of groundwater level on chlorophyll fluorescence characteristics of Tamarix hispida in lower reaches of Tarim River].

    Science.gov (United States)

    Zhu, Cheng-gang; Li, Wei-hong; Ma, Jian-xin; Ma, Xiao-dong

    2010-07-01

    Based on the monitoring data of groundwater level at the typical sections in lower reaches of Tarim River, three survey plots nearby the ecological monitoring wells with groundwater depths > 6 m were selected to investigate the chlorophyll fluorescence characteristics of Tamarix hispida and its photosynthetic activity of PSII under effects of different groundwater depths. With increasing groundwater depth, the chlorophyll fluorescence parameters such as actual photochemical efficiency of PSII in the light (phi(PSII)), electron transport rate (ETR), and photochemistry quenching (q(p)) of T. hispida decreased, while the non-photochemistry quenching (q(N), NPQ) and the yield for dissipation by down-regulation (Y(NPQ)) increased remarkably, and the maximal photochemical efficiency of PSII (Fv/Fm) maintained an optimum value. All the results suggested that the PSII photosynthetic activity of T. hispida under drought stress declined with increasing groundwater depth, and the greater excess energy could result in more risk of photo-inhibition. However, the good adaptability and drought tolerance of T. hispida could make its PSII not seriously damaged, though the drought stress actually existed.

  3. Microbial Community-Level Physiological Profiles (CLPP) and herbicide mineralization potential in groundwater affected by agricultural land use

    Science.gov (United States)

    Janniche, Gry Sander; Spliid, Henrik; Albrechtsen, Hans-Jørgen

    2012-10-01

    Diffuse groundwater pollution from agricultural land use may impact the microbial groundwater community, which was investigated as Community-Level Physiological Profiles (CLPP) using EcoPlate™. Water was sampled from seven piezometers and a spring in a small agricultural catchment with diffuse herbicide and nitrate pollution. Based on the Shannon-Wiener and Simpson's diversity indices the diversity in the microbial communities was high. The response from the EcoPlates™ showed which substrates support groundwater bacteria, and all 31 carbon sources were utilized by organisms from at least one water sample. However, only nine carbon sources were utilized by all water samples: D-Mannitol, N-acetyl-D-glucosamine, putrescine, D-galacturonic acid, itaconic acid, 4-hydroxy benzoic acid, tween 40, tween 80, and L-asparagine. In all water samples the microorganisms preferred D-mannitol, D-galacturonic acid, tween 40, and 4-hydroxy benzoic acid as substrates, whereas none preferred 2-hydroxy benzoic acid, α-D-lactose, D,L-α-glycerol phosphate, α-ketobutyric acid, L-threonine and glycyl-L-glutamic acid. Principal Component Analysis of the CLPP's clustered the most agriculturally affected groundwater samples, indicating that the agricultural land use affects the groundwater microbial communities. Furthermore, the ability to mineralize atrazine and isoproturon, which have been used in the catchment, was also associated with this cluster.

  4. Screening-Level Risk Assessment for Styrene-Acrylonitrile (SAN) Trimer Detected in Soil and Groundwater

    Science.gov (United States)

    Kirman, C. R.; Gargas, M. L.; Collins, J. J.; Rowlands, J. C.

    2012-01-01

    A screening-level risk assessment was conducted for styrene-acrylonitrile (SAN) Trimer detected at the Reich Farm Superfund site in Toms River, NJ. Consistent with a screening-level approach, on-site and off-site exposure scenarios were evaluated using assumptions that are expected to overestimate actual exposures and hazards at the site. Environmental sampling data collected for soil and groundwater were used to estimate exposure point concentrations. Several exposure scenarios were evaluated to assess potential on-site and off-site exposures, using parameter values for exposures to soil (oral, inhalation of particulates, and dermal contact) and groundwater (oral, dermal contact) to reflect central tendency exposure (CTE) and reasonable maximum exposure (RME) conditions. Three reference dose (RfD) values were derived for SAN Trimer for short-term, subchronic, and chronic exposures, based upon its effects on the liver in exposed rats. Benchmark (BMD) methods were used to assess the relationship between exposure and response, and to characterize appropriate points of departure (POD) for each RfD. An uncertainty factor of 300 was applied to each POD to yield RfD values of 0.1, 0.04, and 0.03 mg/kg-d for short-term, subchronic, and chronic exposures, respectively. Because a chronic cancer bioassay for SAN Trimer in rats (NTP 2011a) does not provide evidence of carcinogenicity, a cancer risk assessment is not appropriate for this chemical. Potential health hazards to human health were assessed using a hazard index (HI) approach, which considers the ratio of exposure dose (i.e., average daily dose, mg/kg-d) to toxicity dose (RfD, mg/kg-d) for each scenario. All CTE and RME HI values are well below 1 (where the average daily dose is equivalent to the RfD), indicating that there is no concern for potential noncancer effects in exposed populations even under the conservative assumptions of this screening-level assessment. PMID:23030654

  5. Using Hydrologic Data from Africa in a Senior-Level Course in Groundwater Hydrology (Invited)

    Science.gov (United States)

    Silliman, S. E.

    2010-12-01

    Ongoing research efforts in Benin, West Africa, and Uganda, East Africa, have provided substantial data sets involving groundwater quality, applied geophysics, water use, and response of local populations / government agencies to challenges related to water development, protection and management. Ranging from characterization of coastal salt-water encroachment to a major well field to nitrate and microbial contamination of rural water supplies, these data sets were developed by interdisciplinary / international teams that included both undergraduate and graduate students. The present discussion focuses on the integration of the resulting data sets into a senior-level (and lower-level graduate student) course in Groundwater Hydrology. The data sets are employed in multiple ways, including: (i) support of concepts introduced during lectures, (ii) problem sets involving analysis of the data, and (iii) foundation material for open-ended discussions on comparative water resource strategies in developed and developing countries. Most significant in terms of the use of these data sets to advance educational opportunities, the African case studies have been integrated into semester-long projects completed by teams of students as a significant component of their final grade as well as one of their engineering design experiences used to fulfill ABET requirements. During the 2009-2010 academic year, these data sets (as well as published data bases by other agencies) were used by individual groups to design water development strategies for rural villages. During the present semester, two teams of students are pursuing long-term sustainability analyses, the first focused on an aquifer system in northern Indiana (USA) and the second focused on a coastal aquifer system serving Cotonou, Benin. The goal of pursuing these parallel projects is to illustrate to the students the similarities and differences involved in water resource management / protection in different parts of the

  6. Long-term observations on the influence of groundwater level variations on BTEX concentrations in groundwater; Langzeituntersuchungen zum Einfluss von Grundwasserschwankungen auf die BTEX-Konzentration im Grundwasser

    Energy Technology Data Exchange (ETDEWEB)

    Puettmann, W. [J.W. Goethe-Universitaet Frankfurt a. M., Institut fuer Atmosphaere und Umwelt, AG Umweltanalytik, Frankfurt/Main (Germany); Hettwer, K.; Warrelmann, J. [Universitaet Bremen, Zentrum fuer Umweltforschung und Umwelttechnologie, Bremen (Germany); Gaab, S.

    2007-06-15

    A long-term study on natural attenuation and remediation in soil and groundwater at the former military base Schaeferhof-Sued (Niedersachsen) was performed at a former gasoline filling station. At this locality, a large residual source of benzene, toluene, ethylbenzene, xylenes (BTEX) and additional petroleum hydrocarbons is present in the soil. BTEX-concentrations in the groundwater and their correlation with groundwater level variations were monitored for three years. Within the monitoring period, a very dry summer was recorded, which caused the groundwater level to drop by 1.7 m and the BTEX concentrations to increase from 240 {mu}g/l to 1300 {mu}g/l at the site of contamination. The microbial degradation of BTEX was documented by data on consumption of electron acceptors (oxygen, nitrate or sulphate) and production of reduced products (Fe(II), methane). The degradation is further supported by the detection of metabolites. Therefore, the increasing BTEX concentrations were not a consequence of limited biological degradation. (orig.) [German] Auf dem frueher militaerisch genutzten Gelaende Schaeferhof-Sued (Niedersachsen) wurden im Bereich einer ehemaligen Abfuellstation fuer Kraftstoffe Langzeituntersuchungen zum natuerlichen Schadstoffabbau und -rueckhalt im Boden und Grundwasser durchgefuehrt. Der Standort weist eine hohe Restkontamination der Verbindungen Benzol, Toluol, Ethylbenzol und Xylole (BTEX), sowie Mineraloelkohlenwasserstoffen (MKW) in der ungesaettigten Bodenzone auf. Ueber einen Zeitraum von drei Jahren wurden die BTEX-Konzentrationen im Grundwasser und deren Abhaengigkeit von einer Aenderung des Grundwasserstandes untersucht und eine negative Korrelation der Schadstoffkonzentrationen mit der Hoehe des Grundwasserstandes festgestellt. Im Beobachtungszeitraum lag das sehr trockene Sommerhalbjahr 2003, was im Vergleich zum vorhergehenden Winterhalbjahr eine Absenkung des Grundwasserspiegels um 1,7 m zur Folge hatte und die BTEX-Konzentrationen am

  7. Occurrence, behavior and distribution of high levels of uranium in shallow groundwater at Datong basin, northern China

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ya; Wang, Yanxin, E-mail: yx.wang@cug.edu.cn; Xie, Xianjun

    2014-02-01

    Geochemical investigations of uranium (U) occurrence in the environments were conducted at Datong basin of northern China. The results suggest that U contents were generally < 1 mg/kg for the igneous and metamorphic rocks, typically 2–5 mg/kg for the Carboniferous and Permian sedimentary rocks and around 3 mg/kg for sediments and topsoil, respectively. U in the Quaternary aquifer sediments may be primarily associated with carnotite from the Carboniferous and Permian coal-bearing clastic rocks around the basin. Shallow groundwater had U concentrations of < 0.02–288 μg/L (average 24 μg/L), with 24% of the investigated boreholes above the WHO provisional guideline of 30 μg/L for U in drinking water. Average U concentration for surface water was 5.8 μg/L. In oxidizing waters, uranyl (UO{sub 2}{sup 2+}) species is dominant and strongly adsorbed onto iron (hydro)xides, while it would be preferentially complexed with carbonate in the alkaline groundwater, forming highly soluble uranyl-carbonate complexes at Datong. Under reducing conditions, uranous (U(IV)) species is ready to precipitate or bind to organic matter, therefore having a low mobility. At the study area, high U groundwater (> 30 μg/L) occurs at the alluvial plains due to intermediate redox and enhanced alkaline conditions. The abnormally high levels of U in groundwater (> 100 μg/L) are locally found at the west alluvial plains. By contrast, U co-precipitation with secondary carbonate minerals like Ca{sub 2}UO{sub 2}(CO{sub 3}){sub 3} in the dominant Ca–Mg–Na–HCO{sub 3} type groundwater may prevail at the east alluvial plains. Besides, bedrocks such as Carboniferous and Permian sedimentary rocks, especially the coal-bearing strata which have higher U contents at the west mountain areas may also account for the abnormally high levels of U in groundwater. - Highlights: • High U groundwater occurs at the alluvial plains of Datong basin. • Redox state, complexation and adsorption are responsible

  8. Determining the confidence levels of sensor outputs using neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Broten, G S; Wood, H C [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Electrical Engineering

    1996-12-31

    This paper describes an approach for determining the confidence level of a sensor output using multi-sensor arrays, sensor fusion and artificial neural networks. The authors have shown in previous work that sensor fusion and artificial neural networks can be used to learn the relationships between the outputs of an array of simulated partially selective sensors and the individual analyte concentrations in a mixture of analyses. Other researchers have shown that an array of partially selective sensors can be used to determine the individual gas concentrations in a gaseous mixture. The research reported in this paper shows that it is possible to extract confidence level information from an array of partially selective sensors using artificial neural networks. The confidence level of a sensor output is defined as a numeric value, ranging from 0% to 100%, that indicates the confidence associated with a output of a given sensor. A three layer back-propagation neural network was trained on a subset of the sensor confidence level space, and was tested for its ability to generalize, where the confidence level space is defined as all possible deviations from the correct sensor output. A learning rate of 0.1 was used and no momentum terms were used in the neural network. This research has shown that an artificial neural network can accurately estimate the confidence level of individual sensors in an array of partially selective sensors. This research has also shown that the neural network`s ability to determine the confidence level is influenced by the complexity of the sensor`s response and that the neural network is able to estimate the confidence levels even if more than one sensor is in error. The fundamentals behind this research could be applied to other configurations besides arrays of partially selective sensors, such as an array of sensors separated spatially. An example of such a configuration could be an array of temperature sensors in a tank that is not in

  9. A Practical Algorithm for Reconstructing Level-1 Phylogenetic Networks

    NARCIS (Netherlands)

    K.T. Huber; L.J.J. van Iersel (Leo); S.M. Kelk (Steven); R. Suchecki

    2010-01-01

    htmlabstractRecently much attention has been devoted to the construction of phylogenetic networks which generalize phylogenetic trees in order to accommodate complex evolutionary processes. Here we present an efficient, practical algorithm for reconstructing level-1 phylogenetic networks - a type of

  10. Combining ground-based and airborne EM through Artificial Neural Networks for modelling glacial till under saline groundwater conditions

    DEFF Research Database (Denmark)

    Gunnink, J.L.; Bosch, A.; Siemon, B.

    2012-01-01

    Airborne electromagnetic (AEM) methods supply data over large areas in a cost-effective way. We used ArtificialNeural Networks (ANN) to classify the geophysical signal into a meaningful geological parameter. By using examples of known relations between ground-based geophysical data (in this case...... electrical conductivity, EC, from electrical cone penetration tests) and geological parameters (presence of glacial till), we extracted learning rules that could be applied to map the presence of a glacial till using the EC profiles from the airborne EM data. The saline groundwater in the area was obscuring...

  11. Plant traits in response to raising groundwater levels in wetland restoration : evidence from three case studies

    NARCIS (Netherlands)

    Bodegom, P.M. van; Grootjans, A.P.; Sorrell, B.K.; Bekker, R.M.; Bakker, C.; Ozinga, W.A.; Middleton, B.

    Question: Is raising groundwater tables successful as a wetland restoration strategy? Location: Kennemer dunes, The Netherlands; Moksloot dunes, The Netherlands and Bullock Creek fen, New Zealand. Methods: Generalizations were made by analysing soil dynamics and the responsiveness of integrative

  12. Plant traits in response to raising groundwater levels in wetland restoration: evidence from three case studies

    NARCIS (Netherlands)

    Bodegom, van P.M.; Grootjans, A.P.; Sorrell, B.K.; Bekker, R.M.; Bakker, C.; Ozinga, W.A.

    2006-01-01

    Question: Is raising groundwater tables successful as a wetland restoration strategy? Location: Kennemer dunes, The Netherlands; Moksloot dunes, The Netherlands and Bullock Creek fen, New Zealand. Methods: Generalizations were made by analysing soil dynamics and the responsiveness of integrative

  13. 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

  14. 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

  15. Modelling the response of shallow groundwater levels to combined climate and water-diversion scenarios in Beijing-Tianjin-Hebei Plain, China

    Science.gov (United States)

    Li, Xue; Ye, Si-Yuan; Wei, Ai-Hua; Zhou, Peng-Peng; Wang, Li-Heng

    2017-09-01

    A three-dimensional groundwater flow model was implemented to quantify the temporal variation of shallow groundwater levels in response to combined climate and water-diversion scenarios over the next 40 years (2011-2050) in Beijing-Tianjin-Hebei (Jing-Jin-Ji) Plain, China. Groundwater plays a key role in the water supply, but the Jing-Jin-Ji Plain is facing a water crisis. Groundwater levels have declined continuously over the last five decades (1961-2010) due to extensive pumping and climate change, which has resulted in decreased recharge. The implementation of the South-to-North Water Diversion Project (SNWDP) will provide an opportunity to restore the groundwater resources. The response of groundwater levels to combined climate and water-diversion scenarios has been quantified using a groundwater flow model. The impacts of climate change were based on the World Climate Research Programme's (WCRP's) Coupled Model Intercomparison Project phase 3 (CMIP3) multi-model dataset for future high (A2), medium (A1B), and low (B1) greenhouse gas scenarios; precipitation data from CMIP3 were applied in the model. The results show that climate change will slow the rate of decrease of the shallow groundwater levels under three climate-change scenarios over the next 40 years compared to the baseline scenario; however, the shallow groundwater levels will rise significantly (maximum of 6.71 m) when considering scenarios that combine climate change and restrictions on groundwater exploitation. Restrictions on groundwater exploitation for water resource management are imperative to control the decline of levels in the Jing-Jin-Ji area.

  16. Effects of carbonate and sulphate ions in synthetic groundwater on high-level waste glass leaching

    International Nuclear Information System (INIS)

    Kamizono, H.

    1990-01-01

    This laboratory experiment aims to examine the effects of rare earth carbonate and sulphate ions, that are naturally present in underground water, have on glass used to store high-level radioactive waste for disposal underground. Borosilicate glass (or HLW glass) is stored under observation on the land surface for several decades before being buried deep below ground in geological disposal sites. Two types of precipitation occur during leaching from the glass, immediate formation of a hydrated surface layer and slow precipitation from concentration in the leachates. This slow process of some elements precipitating onto the glass surface or into the leachates is examined in this experiment using scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). Carbonates from rare-earth elements are found in the synthetic groundwater used. It is shown that carbonate and sulphate ions will affect leaching and will occur in geological disposal sites. Other particles were also observed to precipitate using SEM-EDX. (author)

  17. Comparison of specific-yield estimates for calculating evapotranspiration from diurnal groundwater-level fluctuations

    Science.gov (United States)

    Gribovszki, Zoltán

    2018-05-01

    Methods that use diurnal groundwater-level fluctuations are commonly used for shallow water-table environments to estimate evapotranspiration (ET) and recharge. The key element needed to obtain reliable estimates is the specific yield (Sy), a soil-water storage parameter that depends on unsaturated soil-moisture and water-table fluxes, among others. Soil-moisture profile measurement down to the water table, along with water-table-depth measurements, can provide a good opportunity to calculate Sy values even on a sub-daily scale. These values were compared with Sy estimates derived by traditional techniques, and it was found that slug-test-based Sy values gave the most similar results in a sandy soil environment. Therefore, slug-test methods, which are relatively cheap and require little time, were most suited to estimate Sy using diurnal fluctuations. The reason for this is that the timeframe of the slug-test measurement is very similar to the dynamic of the diurnal signal. The dynamic characteristic of Sy was also analyzed on a sub-daily scale (depending mostly on the speed of drainage from the soil profile) and a remarkable difference was found in Sy with respect to the rate of change of the water table. When comparing constant and sub-daily (dynamic) Sy values for ET estimation, the sub-daily Sy application yielded higher correlation, but only a slightly smaller deviation from the control ET method, compared with the usage of constant Sy.

  18. Determining critical groundwater level to prevent degraded peatland from severe peat fire

    Science.gov (United States)

    Putra, E. I.; Cochrane, M. A.; Vetrita, Y.; Graham, L.; Saharjo, B. H.

    2018-05-01

    Peat fires have been a severe recurrent problem for Indonesia, but droughts due to prolonged dry season aggravate burning conditions. To get a better understanding of this issue, we studied fire conditions in a portion of the ex-Mega Rice Project (MRP) area, Central Kalimantan. To examine fire season and hydrology factors affecting peat fires we analyzed daily TRMM data, Nino 3.4 SST Anomalies, and changing groundwater levels (GWL) from 300 dipwells. Our results quantify time-lags between the period of lowest precipitation and the lowest GWL; providing some ability to predict fire risk in advance of the lowest GWL. The rise of Nino 3.4 SST anomalies is significant risk factors for peat fire as they signify dry months which may yield large fire occurrences. GWL in 2011 was lower than in 2012, but fires were more frequent in 2012, indicating that low precipitation amounts in the wet season of 2011/2012 left the peat in a dry condition early in 2012. Most of the fires occurred in areas with GWL less than -30 cm, powerfully illustrating the importance of maintaining GWL at more than -10 cm, to prevent degraded peatlands from experiencing surface and deep peat fires.

  19. System-level Modeling of Wireless Integrated Sensor Networks

    DEFF Research Database (Denmark)

    Virk, Kashif M.; Hansen, Knud; Madsen, Jan

    2005-01-01

    Wireless integrated sensor networks have emerged as a promising infrastructure for a new generation of monitoring and tracking applications. In order to efficiently utilize the extremely limited resources of wireless sensor nodes, accurate modeling of the key aspects of wireless sensor networks...... is necessary so that system-level design decisions can be made about the hardware and the software (applications and real-time operating system) architecture of sensor nodes. In this paper, we present a SystemC-based abstract modeling framework that enables system-level modeling of sensor network behavior...... by modeling the applications, real-time operating system, sensors, processor, and radio transceiver at the sensor node level and environmental phenomena, including radio signal propagation, at the sensor network level. We demonstrate the potential of our modeling framework by simulating and analyzing a small...

  20. Simulation and assessment of groundwater flow and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2003 through 2013: Chapter B of Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

    Science.gov (United States)

    Jones, Perry M.; Roth, Jason L.; Trost, Jared J.; Christenson, Catherine A.; Diekoff, Aliesha L.; Erickson, Melinda L.

    2017-09-05

    Water levels during 2003 through 2013 were less than mean water levels for the period 1925–2013 for several lakes in the northeast Twin Cities Metropolitan Area in Minnesota. Previous periods of low lake-water levels generally were correlated with periods with less than mean precipitation. Increases in groundwater withdrawals and land-use changes have brought into question whether or not recent (2003–13) lake-water-level declines are solely caused by decreases in precipitation. A thorough understanding of groundwater and surface-water exchanges was needed to assess the effect of water-management decisions on lake-water levels. To address this need, the U.S. Geological Survey, in cooperation with the Metropolitan Council and the Minnesota Department of Health, developed and calibrated a three-dimensional, steady-state groundwater-flow model representing 2003–13 mean hydrologic conditions to assess groundwater and lake-water exchanges, and the effects of groundwater withdrawals and precipitation on water levels of 96 lakes in the northeast Twin Cities Metropolitan Area.Lake-water budgets for the calibrated groundwater-flow model indicated that groundwater is flowing into lakes in the northeast Twin Cities Metropolitan Area and lakes are providing water to underlying aquifers. Lake-water outflow to the simulated groundwater system was a major outflow component for Big Marine Lake, Lake Elmo, Snail Lake, and White Bear Lake, accounting for 45 to 64 percent of the total outflows from the lakes. Evaporation and transpiration from the lake surface ranged from 19 to 52 percent of the total outflow from the four lakes. Groundwater withdrawals and precipitation were varied from the 2003‒13 mean values used in the calibrated model (30-percent changes in groundwater withdrawals and 5-percent changes in precipitation) for hypothetical scenarios to assess the effects of groundwater withdrawals and precipitation on water budgets and levels in Big Marine Lake, Snail Lake

  1. [Assessment of shallow groundwater nitrate concentrations in typical terrestrial ecosystems of Chinese Ecosystem Research Network (CERN) during 2004-2009].

    Science.gov (United States)

    Xu, Zhi-Wei; Zhang, Xin-Yu; Sun, Xiao-Min; Yuan, Guo-Fu; Wang, Sheng-Zhong; Liu, Wen-Hua

    2011-10-01

    The nitrate-N (NO3(-) -N) concentrations of 38 shallow groundwater wells from 31 of the typical terrestrial ecosystems on Chinese Ecosystem Research Network (CERN) were assessed using the monitoring data from 2004 to 2009. The results showed that the average values of NO3(-) -N concentrations were significantly higher in the agricultural (4.85 mg x L(-1) +/- 0.42 mg x L(-1)), desert (oasis) (3.72 mg x L(-1) +/- 0.42 mg x L(-1)) and urban ecosystems (3.77 mg x L(-1) 0.51 mg x L(-1)) than in the grass (1.59 mg x L(-1) +/- 0.35 mg L(-1)) and forest ecosystems (0.39 mg x L(-1) +/- 0.03 mg x L(-1)). Nitrate was the major form of nitrogen, with between 56% to 88% of nitrogen in the nitrate-N form in the shallow groundwater of desert (oasis), urban and agricultural ecosystems. Nitrate-N concentrations for some agricultural ecosystems (Ansai, Yanting, Yucheng) and desert (oasis) ecosystems (Cele, Linze, Akesu) analysis exceeded the 10 mg x L(-1) World Health Organization drinking water standards between 14.3% and 84.6%. Significant seasonality was found in Ansai, Fengqiu, Yanting agricultural ecosystems and the Beijing urban ecosystem using the relatively high frequency monitoring data, with the higher nitrate concentrations usually found during summer and winter months. The monitoring results indicated that the shallow groundwater of agricultural ecosystems was contaminated by agricultural management practices, i.e. fertilization, while the shallow groundwater of forest ecosystems was under natural condition with no contamination from human activities.

  2. Enhancement of the FDOT's project level and network level bridge management analysis tools

    Science.gov (United States)

    2011-02-01

    Over several years, the Florida Department of Transportation (FDOT) has been implementing the AASHTO Pontis Bridge Management System to support network-level and project-level decision making in the headquarters and district offices. Pontis is an int...

  3. Sampling history and 2009--2010 results for pesticides and inorganic constituents monitored by the Lake Wales Ridge Groundwater Network, central Florida

    Science.gov (United States)

    Choquette, Anne F.; Freiwald, R. Scott; Kraft, Carol L.

    2012-01-01

    The Lake Wales Ridge Monitoring (LWRM) Network was established to provide a long-term record of water quality of the surficial aquifer in one of the principal citrus-production areas of Florida. This region is underlain by sandy soils that contain minimal organic matter and are highly vulnerable to leaching of chemicals into the subsurface. This report documents the 1989 through May 2010 sampling history of the LWRM Network and summarizes monitoring results for 38 Network wells that were sampled during the period January 2009 through May 2010. During 1989 through May 2010, the Network’s citrus land-use wells were sampled intermittently to 1999, quarterly from April 1999 to October 2009, and thereafter quarterly to semiannually. The water-quality summaries in this report focus on the period January 2009 through May 2010, during which the Network’s citrus land-use wells were sampled six times and the non-citrus land-use wells were sampled two times. Within the citrus land-use wells sampled, a total of 13 pesticide compounds (8 parent pesticides and 5 degradates) were detected of the 37 pesticide compounds analyzed during this period. The most frequently detected compounds included demethyl norflurazon (83 percent of wells), norflurazon (79 percent), aldicarb sulfoxide (41 percent), aldicarb sulfone (38 percent), imidacloprid (38 percent), and diuron (28 percent). Agrichemical concentrations in samples from the citrus land-use wells during the 2009 through May 2010 period exceeded Federal drinking-water standards (maximum contaminant levels, MCLs) in 1.5 to 24 percent of samples for aldicarb and its degradates (sulfone and sulfoxide), and in 68 percent of the samples for nitrate. Florida statutes restrict the distance of aldicarb applications to drinking-water wells; however, these statutes do not apply to monitoring wells. Health-screening benchmark levels that identify unregulated chemicals of potential concern were exceeded for norflurazon and diuron in 29 and

  4. Assessment of Fluoride Level in Groundwater and Prevalence of Dental Fluorosis in Didwana Block of Nagaur District, Central Rajasthan, India

    Directory of Open Access Journals (Sweden)

    M Arif

    2013-10-01

    Full Text Available Background: In India, for the high concentration of fluoride in groundwater, people are at risk of dental fluorosis. The problem is common in various states of India. The condition in Rajasthan is worse where all districts have such a problem. Objective: To study the fluoride concentration in groundwater and prevalence of dental fluorosis in Didwana block of Nagaur district, Central Rajasthan, India. Methods: The fluoride concentration in water of 54 villages was measured electrochemically, using fluoride ion selective electrode. Dental fluorosis was assessed in 1136 people residing in study area by Dean's classification for dental fluorosis. Results: The fluoride concentration in groundwater in studied sites ranged from 0.5 to 8.5 mg/L. The concentration of fluoride was more than the maximum permissible limit set by WHO and Bureau of Indian Standards (1 mg/L in 48 groundwater sources. Of 1136 people studied, 788 (69.4%; 95% CI: 66.7%–72.1% had dental fluorosis—252 had mild and 74 had severe dental fluorosis. Conclusion: High level of fluoride in drinking water of Didwana block of Nagaur district, Central Rajasthan, India, causes dental fluorosis in most people in the region and is an important health problem that needs prompt attention.

  5. The Unified Levelling Network of Sarawak and its Adjustment

    Science.gov (United States)

    Som, Z. A. M.; Yazid, A. M.; Ming, T. K.; Yazid, N. M.

    2016-09-01

    The height reference network of Sarawak has seen major improvement in over the past two decades. The most significant improvement was the establishment of extended precise leveling network of which is now able to connect all three major datum points at Pulau Lakei, Original and Bintulu. Datum by following the major accessible routes across Sarawak. This means the leveling network in Sarawak has now been inter-connected and unified. By having such a unified network leads to the possibility of having a common single least squares adjustment been performed for the first time. The least squares adjustment of this unified levelling network was attempted in order to compute the height of all Bench Marks established in the entire levelling network. The adjustment was done by using MoreFix levelling adjustment package developed at FGHT UTM. The computational procedure adopted is linear parametric adjustment by minimum constraint. Since Sarawak has three separate datums therefore three separate adjustments were implemented by utilizing datum at Pulau Lakei, Original Miri and Bintulu Datum respectively. Results of the MoreFix unified adjustment agreed very well with adjustment repeated using Starnet. Further the results were compared with solution given by Jupem and they are in good agreement as well. The difference in height analysed were within 10mm for the case of minimum constraint at Pulau Lakei datum and with much better agreement in the case of Original Miri Datum.

  6. THE UNIFIED LEVELLING NETWORK OF SARAWAK AND ITS ADJUSTMENT

    Directory of Open Access Journals (Sweden)

    Z. A. M. Som

    2016-09-01

    Full Text Available The height reference network of Sarawak has seen major improvement in over the past two decades. The most significant improvement was the establishment of extended precise leveling network of which is now able to connect all three major datum points at Pulau Lakei, Original and Bintulu. Datum by following the major accessible routes across Sarawak. This means the leveling network in Sarawak has now been inter-connected and unified. By having such a unified network leads to the possibility of having a common single least squares adjustment been performed for the first time. The least squares adjustment of this unified levelling network was attempted in order to compute the height of all Bench Marks established in the entire levelling network. The adjustment was done by using MoreFix levelling adjustment package developed at FGHT UTM. The computational procedure adopted is linear parametric adjustment by minimum constraint. Since Sarawak has three separate datums therefore three separate adjustments were implemented by utilizing datum at Pulau Lakei, Original Miri and Bintulu Datum respectively. Results of the MoreFix unified adjustment agreed very well with adjustment repeated using Starnet. Further the results were compared with solution given by Jupem and they are in good agreement as well. The difference in height analysed were within 10mm for the case of minimum constraint at Pulau Lakei datum and with much better agreement in the case of Original Miri Datum.

  7. Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

    Science.gov (United States)

    Jones, Perry M.; Trost, Jared J.; Erickson, Melinda L.

    2016-10-19

    OverviewThis study assessed lake-water levels and regional and local groundwater and surface-water exchanges near northeast Twin Cities Metropolitan Area lakes applying three approaches: statistical analysis, field study, and groundwater-flow modeling.  Statistical analyses of lake levels were completed to assess the effect of physical setting and climate on lake-level fluctuations of selected lakes. A field study of groundwater and surface-water interactions in selected lakes was completed to (1) estimate potential percentages of surface-water contributions to well water across the northeast Twin Cities Metropolitan Area, (2) estimate general ages for waters extracted from the wells, and (3) assess groundwater inflow to lakes and lake-water outflow to aquifers downgradient from White Bear Lake.  Groundwater flow was simulated using a steady-state, groundwater-flow model to assess regional groundwater and surface-water exchanges and the effects of groundwater withdrawals, climate, and other factors on water levels of northeast Twin Cities Metropolitan Area lakes.

  8. Quantification of groundwater infiltration and surface water inflows in urban sewer networks based on a multiple model approach.

    Science.gov (United States)

    Karpf, Christian; Krebs, Peter

    2011-05-01

    The management of sewer systems requires information about discharge and variability of typical wastewater sources in urban catchments. Especially the infiltration of groundwater and the inflow of surface water (I/I) are important for making decisions about the rehabilitation and operation of sewer networks. This paper presents a methodology to identify I/I and estimate its quantity. For each flow fraction in sewer networks, an individual model approach is formulated whose parameters are optimised by the method of least squares. This method was applied to estimate the contributions to the wastewater flow in the sewer system of the City of Dresden (Germany), where data availability is good. Absolute flows of I/I and their temporal variations are estimated. Further information on the characteristics of infiltration is gained by clustering and grouping sewer pipes according to the attributes construction year and groundwater influence and relating these resulting classes to infiltration behaviour. Further, it is shown that condition classes based on CCTV-data can be used to estimate the infiltration potential of sewer pipes. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Investigation of the climate-driven periodicity of shallow groundwater level fluctuations in a Central-Eastern European agricultural region

    Science.gov (United States)

    Garamhegyi, Tamás; Kovács, József; Pongrácz, Rita; Tanos, Péter; Hatvani, István Gábor

    2018-05-01

    The distribution and amount of groundwater, a crucial source of Earth's drinking and irrigation water, is changing due to climate-change effects. Therefore, it is important to understand groundwater behavior in extreme scenarios, e.g. drought. Shallow groundwater (SGW) level fluctuation under natural conditions displays periodic behavior, i.e. seasonal variation. Thus, the study aims to investigate (1) the periodic behavior of the SGW level time series of an agriculturally important and drought-sensitive region in Central-Eastern Europe - the Carpathian Basin, in the north-eastern part of the Great Hungarian Plain, and (2) its relationship to the European atmospheric pressure action centers. Data from 216 SGW wells were studied using wavelet spectrum analysis and wavelet coherence analyses for 1961-2010. Locally, a clear relationship exists between the absence of annual periodic behavior in the SGW level and the periodicity of droughts, as indicated by the self-calibrating Palmer Drought Severity Index and the Aridity Index. During the non-periodic intervals, significant drops in groundwater levels (average 0.5 m) were recorded in 89% of the wells. This result links the meteorological variables to the periodic behavior of SGW, and consequently, drought. On a regional scale, Mediterranean cyclones from the Gulf of Genoa (northwest Italy) were found to be a driving factor in the 8-yr periodic behavior of the SGW wells. The research documents an important link between SGW levels and local/regional climate variables or indices, thereby facilitating the necessary adaptation strategies on national and/or regional scales, as these must take into account the predictions of drought-related climatic conditions.

  10. Plants as bio-indicators of subsurface conditions: impact of groundwater level on BTEX concentrations in trees.

    Science.gov (United States)

    Wilson, Jordan; Bartz, Rachel; Limmer, Matt; Burken, Joel

    2013-01-01

    Numerous studies have demonstrated trees' ability to extract and translocate moderately hydrophobic contaminants, and sampling trees for compounds such as BTEX can help delineate plumes in the field. However, when BTEX is detected in the groundwater, detection in nearby trees is not as reliable an indicator of subsurface contamination as other compounds such as chlorinated solvents. Aerobic rhizospheric and bulk soil degradation is a potential explanation for the observed variability of BTEX in trees as compared to groundwater concentrations. The goal of this study was to determine the effect of groundwater level on BTEX concentrations in tree tissue. The central hypothesis was increased vadose zone thickness promotes biodegradation of BTEX leading to lower BTEX concentrations in overlying trees. Storage methods for tree core samples were also investigated as a possible reason for tree cores revealing lower than expected BTEX levels in some sampling efforts. The water level hypothesis was supported in a greenhouse study, where water table level was found to significantly affect tree BTEX concentrations, indicating that the influx of oxygen coupled with the presence of the tree facilitates aerobic biodegradation of BTEX in the vadose zone.

  11. Geostatistical interpolation model selection based on ArcGIS and spatio-temporal variability analysis of groundwater level in piedmont plains, northwest China.

    Science.gov (United States)

    Xiao, Yong; Gu, Xiaomin; Yin, Shiyang; Shao, Jingli; Cui, Yali; Zhang, Qiulan; Niu, Yong

    2016-01-01

    Based on the geo-statistical theory and ArcGIS geo-statistical module, datas of 30 groundwater level observation wells were used to estimate the decline of groundwater level in Beijing piedmont. Seven different interpolation methods (inverse distance weighted interpolation, global polynomial interpolation, local polynomial interpolation, tension spline interpolation, ordinary Kriging interpolation, simple Kriging interpolation and universal Kriging interpolation) were used for interpolating groundwater level between 2001 and 2013. Cross-validation, absolute error and coefficient of determination (R(2)) was applied to evaluate the accuracy of different methods. The result shows that simple Kriging method gave the best fit. The analysis of spatial and temporal variability suggest that the nugget effects from 2001 to 2013 were increasing, which means the spatial correlation weakened gradually under the influence of human activities. The spatial variability in the middle areas of the alluvial-proluvial fan is relatively higher than area in top and bottom. Since the changes of the land use, groundwater level also has a temporal variation, the average decline rate of groundwater level between 2007 and 2013 increases compared with 2001-2006. Urban development and population growth cause over-exploitation of residential and industrial areas. The decline rate of the groundwater level in residential, industrial and river areas is relatively high, while the decreasing of farmland area and development of water-saving irrigation reduce the quantity of water using by agriculture and decline rate of groundwater level in agricultural area is not significant.

  12. Spatial analysis of groundwater levels using Fuzzy Logic and geostatistical tools

    Science.gov (United States)

    Theodoridou, P. G.; Varouchakis, E. A.; Karatzas, G. P.

    2017-12-01

    The spatial variability evaluation of the water table of an aquifer provides useful information in water resources management plans. Geostatistical methods are often employed to map the free surface of an aquifer. In geostatistical analysis using Kriging techniques the selection of the optimal variogram is very important for the optimal method performance. This work compares three different criteria to assess the theoretical variogram that fits to the experimental one: the Least Squares Sum method, the Akaike Information Criterion and the Cressie's Indicator. Moreover, variable distance metrics such as the Euclidean, Minkowski, Manhattan, Canberra and Bray-Curtis are applied to calculate the distance between the observation and the prediction points, that affects both the variogram calculation and the Kriging estimator. A Fuzzy Logic System is then applied to define the appropriate neighbors for each estimation point used in the Kriging algorithm. The two criteria used during the Fuzzy Logic process are the distance between observation and estimation points and the groundwater level value at each observation point. The proposed techniques are applied to a data set of 250 hydraulic head measurements distributed over an alluvial aquifer. The analysis showed that the Power-law variogram model and Manhattan distance metric within ordinary kriging provide the best results when the comprehensive geostatistical analysis process is applied. On the other hand, the Fuzzy Logic approach leads to a Gaussian variogram model and significantly improves the estimation performance. The two different variogram models can be explained in terms of a fractional Brownian motion approach and of aquifer behavior at local scale. Finally, maps of hydraulic head spatial variability and of predictions uncertainty are constructed for the area with the two different approaches comparing their advantages and drawbacks.

  13. Assessment of the impact of sea-level rise due to climate change on coastal groundwater discharge.

    Science.gov (United States)

    Masciopinto, Costantino; Liso, Isabella Serena

    2016-11-01

    An assessment of sea intrusion into coastal aquifers as a consequence of local sea-level rise (LSLR) due to climate change was carried out at Murgia and Salento in southern Italy. The interpolation of sea-level measurements at three tide-gauge stations was performed during the period of 2000 to 2014. The best fit of measurements shows an increasing rate of LSLR ranging from 4.4mm/y to 8.8mm/y, which will result in a maximum LSLR of approximately 2m during the 22nd century. The local rate of sea-level rise matches recent 21st and 22nd century projections of mean global sea-level rise determined by other researchers, which include increased melting rates of the Greenland and Antarctic ice sheets, the effect of ocean thermal expansion, the melting of glaciers and ice caps, and changes in the quantity of stored land water. Subsequently, Ghyben-Herzberg's equation for the freshwater/saltwater interface was rewritten in order to determine the decrease in groundwater discharge due to the maximum LSLR. Groundwater flow simulations and ArcGIS elaborations of digital elevation models of the coast provided input data for the Ghyben-Herzberg calculation under the assumption of head-controlled systems. The progression of seawater intrusion due to LSLR suggests an impressive depletion of available groundwater discharge during the 22nd century, perhaps as much as 16.1% of current groundwater pumping for potable water in Salento. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Groundwater level variations in the seismically active region of Western Bohemia in the years 2005-2010

    Czech Academy of Sciences Publication Activity Database

    Gaždová, Renata; Novotný, Oldřich; Málek, Jiří; Valenta, Jan; Brož, Milan; Kolínský, Petr

    2011-01-01

    Roč. 8, č. 1 (2011), s. 17-27 ISSN 1214-9705 R&D Projects: GA AV ČR IAA300460602 Institutional research plan: CEZ:AV0Z30460519 Keywords : Western Bohemia * earthquake swarm * groundwater level Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.530, year: 2011 http://www.irsm.cas.cz/abstracts/AGG/01_11/2_Gazdova.pdf

  15. Seismicity, groundwater level variations and Earth tides in the Hronov-Poříčí Fault Zone, Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Kolínský, Petr; Valenta, Jan; Gaždová, Renata

    2012-01-01

    Roč. 9, č. 2 (2012), s. 191-209 ISSN 1214-9705 R&D Projects: GA ČR GA205/09/1244 Institutional research plan: CEZ:AV0Z30460519 Keywords : Eastern Bohemian Massif * groundwater level * seismic ity Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.530, year: 2011 http://www.irsm.cas.cz/materialy/acta_content/2012_02/9_Kolinsky.pdf

  16. Distributed applications monitoring at system and network level

    CERN Document Server

    Aderholz, Michael; Augé, E; Bagliesi, G; Banistoni, G; Barone, L; Boschini, M; Brunengo, A; Bunn, J J; Butler, J; Campanella, M; Capiluppi, P; D'Amato, M; Darneri, M; Di Mattia, A; Dorokhov, A E; Gagliardi, F; Gaines, I; Gasparini, U; Ghiselli, A; Gordon, J; Grandi, C; Gálvez, P; Harris, F; Holtman, K; Karimäki, V; Karita, Y; Klem, J T; Legrand, I; Leltchouk, M; Linglin, D; Lubrano, P; Luminari, L; McArthur, I C; Michelotto, M; Morita, Y; Nazarenko, A; Newman, H; O'Dell, Vivian; O'Neale, S W; Osculati, B; Pepé, M; Perini, L; Pinfold, James L; Pordes, R; Prelz, F; Putzer, A; Resconi, S; Robertson, L; Rolli, S; Sasaki, T; Sato, H; Schaffer, R D; Schalk, T L; Servoli, L; Sgaravatto, M; Shiers, J; Silvestris, L; Siroli, G P; Sliwa, K; Smith, T; Somigliana, R; Stanescu, C; Stockinger, H E; Ugolotti, D; Valente, E; Vistoli, C; Wilkinson, R P; Willers, Ian Malcolm; Williams, D O

    2001-01-01

    Most distributed applications are based on architectural models that do not involve real-time knowledge of network status and of their network usage. Moreover the new "network aware" architectures are still under development and their design is not yet complete. We considered, as a use case, an application using ODBMS (Objectivity /DB) for the distributed analysis of experimental data. The dynamic usage of system and network resources at host and application levels has been measured in different client/server configurations, and on several LAN and WAN layouts. The aim was to study the application efficiency and behavior versus the network characteristics and conditions. The most interesting results of the LAN and WAN tests are described. System bottlenecks and limitations have been identified, and efficient working conditions in the different scenarios have been defined. The behavior observed when moving away from the optimal working conditions is also described.

  17. Interaction of Peat Soil and Sulphidic Material Substratum: Role of Peat Layer and Groundwater Level Fluctuations on Phosphorus Concentration

    Directory of Open Access Journals (Sweden)

    Benito Heru Purwanto

    2014-09-01

    Full Text Available Phosphorus (P often becomes limiting factor for plants growth. Phosphorus geochemistry in peatland soil is associated with the presence of peat layer and groundwater level fluctuations. The research was conducted to study the role of peat layer and groundwater level fluctuations on P concentration in peatland. The research was conducted on deep, moderate and shallow peat with sulphidic material as substratum, peaty acid sulphate soil, and potential acid sulphate soil. While P concentration was observed in wet season, in transition from wet to dry season, and in dry season. Soil samples were collected by using peat borer according to interlayer and soil horizon. The results showed that peat layer might act as the main source of P in peatland with sulphidic material substratum. The upper peat layer on sulphidic material caused by groundwater level fluctuations had no directly effect on P concentration in the peat layers. Increased of P concentration in the lowest sulphidic layer might relate to redox reaction of iron in the sulphidic layer and precipitation process. Phosphorus concentration in peatland with sulphidic material as substratum was not influenced by peat thickness. However, depletion or disappearance of peat layer decreased P concentration in soil solution. Disappearance of peat layer means loss of a natural source of P for peatland with sulphidic material as substratum, therefore peat layer must be kept in order to maintain of peatlands.

  18. Predicted impacts of future water level decline on monitoring wells using a ground-water model of the Hanford Site

    International Nuclear Information System (INIS)

    Wurstner, S.K.; Freshley, M.D.

    1994-12-01

    A ground-water flow model was used to predict water level decline in selected wells in the operating areas (100, 200, 300, and 400 Areas) and the 600 Area. To predict future water levels, the unconfined aquifer system was stimulated with the two-dimensional version of a ground-water model of the Hanford Site, which is based on the Coupled Fluid, Energy, and Solute Transport (CFEST) Code in conjunction with the Geographic Information Systems (GIS) software package. The model was developed using the assumption that artificial recharge to the unconfined aquifer system from Site operations was much greater than any natural recharge from precipitation or from the basalt aquifers below. However, artificial recharge is presently decreasing and projected to decrease even more in the future. Wells currently used for monitoring at the Hanford Site are beginning to go dry or are difficult to sample, and as the water table declines over the next 5 to 10 years, a larger number of wells is expected to be impacted. The water levels predicted by the ground-water model were compared with monitoring well completion intervals to determine which wells will become dry in the future. Predictions of wells that will go dry within the next 5 years have less uncertainty than predictions for wells that will become dry within 5 to 10 years. Each prediction is an estimate based on assumed future Hanford Site operating conditions and model assumptions

  19. The contribution of geology and groundwater studies to city-scale ground heat network strategies: A case study from Cardiff, UK

    Science.gov (United States)

    Boon, David; Farr, Gareth; Patton, Ashley; Kendall, Rhian; James, Laura; Abesser, Corinna; Busby, Jonathan; Schofield, David; White, Debbie; Gooddy, Daren; James, David; Williams, Bernie; Tucker, David; Knowles, Steve; Harcombe, Gareth

    2016-04-01

    The development of integrated heat network strategies involving exploitation of the shallow subsurface requires knowledge of ground conditions at the feasibility stage, and throughout the life of the system. We describe an approach to the assessment of ground constraints and energy opportunities in data-rich urban areas. Geological and hydrogeological investigations have formed a core component of the strategy development for sustainable thermal use of the subsurface in Cardiff, UK. We present findings from a 12 month project titled 'Ground Heat Network at a City Scale', which was co-funded by NERC/BGS and the UK Government through the InnovateUK Energy Catalyst grant in 2015-16. The project examined the technical feasibility of extracting low grade waste heat from a shallow gravel aquifer using a cluster of open loop ground source heat pumps. Heat demand mapping was carried out separately. The ground condition assessment approach involved the following steps: (1) city-wide baseline groundwater temperature mapping in 2014 with seasonal monitoring for at least 12 months prior to heat pump installation (Patton et al 2015); (2) desk top and field-based investigation of the aquifer system to determine groundwater levels, likely flow directions, sustainable pumping yields, water chemistry, and boundary conditions; (3) creation of a 3D geological framework model with physical property testing and model attribution; (4) use steps 1-3 to develop conceptual ground models and production of maps and GIS data layers to support scenario planning, and initial heat network concept designs; (5) heat flow modelling in FEFLOW software to analyse sustainability and predict potential thermal breakthrough in higher risk areas; (6) installation of a shallow open loop GSHP research observatory with real-time monitoring of groundwater bodies to provide data for heat flow model validation and feedback for system control. In conclusion, early ground condition modelling and subsurface

  20. Assessment of groundwater management at Hanford

    International Nuclear Information System (INIS)

    Deju, R.A.

    1975-01-01

    A comprehensive review of the groundwater management and environmental monitoring programs at the Hanford reservation was initiated in 1973. A large number of recommendations made as a result of this review are summarized. The purpose of the Hanford Hydrology Program is to maintain a groundwater surveillance network to assess contamination of the natural water system. Potential groundwater contamination is primarily a function of waste management decisions. The review revealed that although the hydrology program would greatly benefit from additional improvements, it is adequate to predict levels of contaminants present in the groundwater system. Studies are presently underway to refine advanced mathematical models to use results of the hydrologic investigation in forecasting the response of the system to different long-term management decisions. No information was found which indicates that a hazard through the groundwater pathway presently exists as a result of waste operations at Hanford. (CH)

  1. Installation of a groundwater monitoring-well network on the east side of the Uncompahgre River in the Lower Gunnison River Basin, Colorado, 2014

    Science.gov (United States)

    Thomas, Judith C.

    2015-10-07

    The east side of the Uncompahgre River Basin has been a known contributor of dissolved selenium to recipient streams. Discharge of groundwater containing dissolved selenium contributes to surface-water selenium concentrations and loads; however, the groundwater system on the east side of the Uncompahgre River Basin is not well characterized. The U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board and the Bureau of Reclamation, has established a groundwater-monitoring network on the east side of the Uncompahgre River Basin. Thirty wells total were installed for this project: 10 in 2012 (DS 923, http://dx.doi.org/10.3133/ds923), and 20 monitoring wells were installed during April and June 2014 which are presented in this report. This report presents location data, lithologic logs, well-construction diagrams, and well-development information. Understanding the groundwater system can provide managers with an additional metric for evaluating the effectiveness of salinity and selenium control projects.

  2. Regulatory networks, legal federalism, and multi-level regulatory systems

    OpenAIRE

    Kerber, Wolfgang; Wendel, Julia

    2016-01-01

    Transnational regulatory networks play important roles in multi-level regulatory regimes, as e.g, the European Union. In this paper we analyze the role of regulatory networks from the perspective of the economic theory of legal federalism. Often sophisticated intermediate institutional solutions between pure centralisation and pure decentralisation can help to solve complex tradeoff problems between the benefits and problems of centralised and decentralised solutions. Drawing upon the insight...

  3. Transfer of European Approach to Groundwater Monitoring in China

    Science.gov (United States)

    Zhou, Y.

    2007-12-01

    Major groundwater development in North China has been a key factor in the huge economic growth and the achievement of self sufficiency in food production. Groundwater accounts for more than 70 percent of urban water supply and provides important source of irrigation water during dry period. This has however caused continuous groundwater level decline and many associated problems: hundreds of thousands of dry wells, dry river beds, land subsidence, seawater intrusion and groundwater quality deterioration. Groundwater levels in the shallow unconfined aquifers have fallen 10m up to 50m, at an average rate of 1m/year. In the deep confined aquifers groundwater levels have commonly fallen 30m up to 90m, at an average rate of 3 to 5m/year. Furthermore, elevated nitrate concentrations have been found in shallow groundwater in large scale. Pesticides have been detected in vulnerable aquifers. Urgent actions are necessary for aquifer recovery and mitigating groundwater pollution. Groundwater quantity and quality monitoring plays a very important role in formulating cost-effective groundwater protection strategies. In 2000 European Union initiated a Water Framework Directive (2000/60/EC) to protect all waters in Europe. The objective is to achieve good water and ecological status by 2015 cross all member states. The Directive requires monitoring surface and groundwater in all river basins. A guidance document for monitoring was developed and published in 2003. Groundwater monitoring programs are distinguished into groundwater level monitoring and groundwater quality monitoring. Groundwater quality monitoring is further divided into surveillance monitoring and operational monitoring. The monitoring guidance specifies key principles for the design and operation of monitoring networks. A Sino-Dutch cooperation project was developed to transfer European approach to groundwater monitoring in China. The project aims at building a China Groundwater Information Centre. Case studies

  4. Interaction Networks: Generating High Level Hints Based on Network Community Clustering

    Science.gov (United States)

    Eagle, Michael; Johnson, Matthew; Barnes, Tiffany

    2012-01-01

    We introduce a novel data structure, the Interaction Network, for representing interaction-data from open problem solving environment tutors. We show how using network community detecting techniques are used to identify sub-goals in problems in a logic tutor. We then use those community structures to generate high level hints between sub-goals.…

  5. Water level observations from Unmanned Aerial Vehicles for improving estimates of surface water-groundwater interaction

    DEFF Research Database (Denmark)

    Bandini, Filippo; Butts, Michael; Vammen Jacobsen, Torsten

    2017-01-01

    spatial resolution; ii) spatially continuous profiles along or across the water body; iii) flexible timing of sampling. A semi-synthetic study was conducted to analyse the value of the new UAV-borne datatype for improving hydrological models, in particular estimates of GW (Groundwater)- SW (Surface Water...

  6. Perennial filter strips reduce nitrate levels in soil and shallow groundwater after grassland-to-cropland conversion.

    Science.gov (United States)

    Zhou, Xiaobo; Helmers, Matthew J; Asbjornsen, Heidi; Kolka, Randy; Tomer, Mark D

    2010-01-01

    Many croplands planted to perennial grasses under the Conservation Reserve Program are being returned to crop production, and with potential consequences for water quality. The objective of this study was to quantify the impact of grassland-to-cropland conversion on nitrate-nitrogen (NO3-N) concentrations in soil and shallow groundwater and to assess the potential for perennial filter strips (PFS) to mitigate increases in NO3-N levels. The study, conducted at the Neal Smith National Wildlife Refuge (NSNWR) in central Iowa, consisted of a balanced incomplete block design with 12 watersheds and four watershed-scale treatments having different proportions and topographic positions of PFS planted in native prairie grasses: 100% rowcrop, 10% PFS (toeslope position), 10% PFS (distributed on toe and as contour strips), and 20 PFS (distributed on toe and as contour strips). All treatments were established in fall 2006 on watersheds that were under bromegrass (Bromus L.) cover for at least 10 yr. Nonperennial areas were maintained under a no-till 2-yr corn (Zea mays L.)--soybean [Glycine max. (L.) Merr.] rotation since spring 2007. Suction lysimeter and shallow groundwater wells located at upslope and toeslope positions were sampled monthly during the growing season to determine NO3-N concentration from 2005 to 2008. The results indicated significant increases in NO3-N concentration in soil and groundwater following grassland-to-cropland conversion. Nitrate-nitrogen levels in the vadose zone and groundwater under PFS were lower compared with 100% cropland, with the most significant differences occurring at the toeslope position. During the years following conversion, PFS mitigated increases in subsurface nitrate, but long-term monitoring is needed to observe and understand the full response to land-use conversion.

  7. Hydrogeology, groundwater levels, and generalized potentiometric-surface map of the Green River Basin lower Tertiary aquifer system, 2010–14, in the northern Green River structural basin

    Science.gov (United States)

    Bartos, Timothy T.; Hallberg, Laura L.; Eddy-Miller, Cheryl

    2015-07-14

    In cooperation with the Bureau of Land Management, groundwater levels in wells located in the northern Green River Basin in Wyoming, an area of ongoing energy development, were measured by the U.S. Geological Survey from 2010 to 2014. The wells were completed in the uppermost aquifers of the Green River Basin lower Tertiary aquifer system, which is a complex regional aquifer system that provides water to most wells in the area. Except for near perennial streams, groundwater-level altitudes in most aquifers generally decreased with increasing depth, indicating a general downward potential for groundwater movement in the study area. Drilled depth of the wells was observed as a useful indicator of depth to groundwater such that deeper wells typically had a greater depth to groundwater. Comparison of a subset of wells included in this study that had historical groundwater levels that were measured during the 1960s and 1970s and again between 2012 and 2014 indicated that, overall, most of the wells showed a net decline in groundwater levels.

  8. Determining the confidence levels of sensor outputs using neural networks

    International Nuclear Information System (INIS)

    Broten, G.S.; Wood, H.C.

    1995-01-01

    This paper describes an approach for determining the confidence level of a sensor output using multi-sensor arrays, sensor fusion and artificial neural networks. The authors have shown in previous work that sensor fusion and artificial neural networks can be used to learn the relationships between the outputs of an array of simulated partially selective sensors and the individual analyte concentrations in a mixture of analyses. Other researchers have shown that an array of partially selective sensors can be used to determine the individual gas concentrations in a gaseous mixture. The research reported in this paper shows that it is possible to extract confidence level information from an array of partially selective sensors using artificial neural networks. The confidence level of a sensor output is defined as a numeric value, ranging from 0% to 100%, that indicates the confidence associated with a output of a given sensor. A three layer back-propagation neural network was trained on a subset of the sensor confidence level space, and was tested for its ability to generalize, where the confidence level space is defined as all possible deviations from the correct sensor output. A learning rate of 0.1 was used and no momentum terms were used in the neural network. This research has shown that an artificial neural network can accurately estimate the confidence level of individual sensors in an array of partially selective sensors. This research has also shown that the neural network's ability to determine the confidence level is influenced by the complexity of the sensor's response and that the neural network is able to estimate the confidence levels even if more than one sensor is in error. The fundamentals behind this research could be applied to other configurations besides arrays of partially selective sensors, such as an array of sensors separated spatially. An example of such a configuration could be an array of temperature sensors in a tank that is not in

  9. A Network Perspective on Individual-Level Ambidexterity in Organizations

    DEFF Research Database (Denmark)

    Rogan, Michelle; Mors, Marie Louise

    2014-01-01

    in the internal and external networks of 79 senior managers in a management consulting firm revealed significant differences in the density, contact heterogeneity, and informality of ties in the networks of senior managers who engaged in both exploration and exploitation compared with managers that predominately......Addressing the call for a deeper understanding of ambidexterity at the individual level, we propose that managers’ networks are an important yet understudied factor in the ability to balance the trade-off between exploring for new business and exploiting existing business. Analyses of 1,449 ties...... explored or exploited. The findings suggest that managers’ networks are important levers for their ability to behave ambidextrously and offer insights into the microfoundations of organizational ambidexterity....

  10. Functional gene array-based analysis of microbial community structure in groundwaters with a gradient of contaminant levels

    Energy Technology Data Exchange (ETDEWEB)

    Waldron, P.J.; Wu, L.; Van Nostrand, J.D.; Schadt, C.W.; Watson, D.B.; Jardine, P.M.; Palumbo, A.V.; Hazen, T.C.; Zhou, J.

    2009-06-15

    To understand how contaminants affect microbial community diversity, heterogeneity, and functional structure, six groundwater monitoring wells from the Field Research Center of the U.S. Department of Energy Environmental Remediation Science Program (ERSP; Oak Ridge, TN), with a wide range of pH, nitrate, and heavy metal contamination were investigated. DNA from the groundwater community was analyzed with a functional gene array containing 2006 probes to detect genes involved in metal resistance, sulfate reduction, organic contaminant degradation, and carbon and nitrogen cycling. Microbial diversity decreased in relation to the contamination levels of the wells. Highly contaminated wells had lower gene diversity but greater signal intensity than the pristine well. The microbial composition was heterogeneous, with 17-70% overlap between different wells. Metal-resistant and metal-reducing microorganisms were detected in both contaminated and pristine wells, suggesting the potential for successful bioremediation of metal-contaminated groundwaters. In addition, results of Mantel tests and canonical correspondence analysis indicate that nitrate, sulfate, pH, uranium, and technetium have a significant (p < 0.05) effect on microbial community structure. This study provides an overall picture of microbial community structure in contaminated environments with functional gene arrays by showing that diversity and heterogeneity can vary greatly in relation to contamination.

  11. Achieving Network Level Privacy in Wireless Sensor Networks†

    Science.gov (United States)

    Shaikh, Riaz Ahmed; Jameel, Hassan; d’Auriol, Brian J.; Lee, Heejo; Lee, Sungyoung; Song, Young-Jae

    2010-01-01

    Full network level privacy has often been categorized into four sub-categories: Identity, Route, Location and Data privacy. Achieving full network level privacy is a critical and challenging problem due to the constraints imposed by the sensor nodes (e.g., energy, memory and computation power), sensor networks (e.g., mobility and topology) and QoS issues (e.g., packet reach-ability and timeliness). In this paper, we proposed two new identity, route and location privacy algorithms and data privacy mechanism that addresses this problem. The proposed solutions provide additional trustworthiness and reliability at modest cost of memory and energy. Also, we proved that our proposed solutions provide protection against various privacy disclosure attacks, such as eavesdropping and hop-by-hop trace back attacks. PMID:22294881

  12. Network Physics anounces first product to provide business-level management of the most complex and dynamic networks

    CERN Multimedia

    2003-01-01

    Network Physics, provider of business-level, traffic flow-based network management solutions, today announced the introduction of the Network Physics NP/BizFlow-1000. With the NP/BizFlow-1000, Fortune 1000 companies with complex and dynamic networks can analyze the flows that link business groups, critical applications, and network software and hardware (1 page).

  13. A Low-Level Real-Time In Situ Monitoring System for Tritium in Groundwater and Vadose Zone

    Science.gov (United States)

    Santo, J. T.; Levitt, D. G.

    2002-12-01

    Tritium is a radioactive isotope of hydrogen produced as a by-product of the nuclear fuel cycle. It is also an integral part of the nuclear weapons industry and has been released into the environment through both the production and testing of nuclear weapons. There are many sites across the DOE complex where tritium has been released into the subsurface through the disposal of radioactive waste and at the Nevada Test Site, through the underground testing of nuclear weapons. Numerous DOE facilities have an on-going regulatory need to be able to monitor tritium concentrations in groundwater within deep hydrologic zones and in the shallower non-saturated vadose zone beneath waste disposal pits and shafts and other release sites. Typical access to groundwater is through deep monitoring wells and situated in remote locations. In response to this need, Science and Engineering Associates, Inc. (SEA) and its subcontractor, the University of Nevada Las Vegas (UNLV) Harry Reid Center (HRC) for Environmental Studies has conducted the applied research and engineering and produced a real time, in situ monitoring system for the detection and measurement of low levels of tritium in the groundwater and in the shallower vadose zone. The monitoring system has been deployed to measure tritium in both the vadose zone near a subsurface radioactive waste package and the groundwater in a deep hydrologic reservoir at the Nevada Test Site. The monitoring system has been designed to detect tritium in the subsurface below federal and/or state regulatory limits for safe drinking water and has been successfully demonstrated. The development effort is being funded through the U.S. Department of Energy, National Energy Technology Laboratory and the DOE Nevada Operations Office Advanced Monitoring Systems Initiative (AMSI).

  14. Enhancing arsenic removal from groundwater at household level with naturally occurring iron

    Directory of Open Access Journals (Sweden)

    Anitha Kumari Sharma

    2016-06-01

    Full Text Available A supply of drinking water low in Arsenic (As prevents arsenic poisoning. The presence of high concentrations of iron (Fe in groundwater under the alluvial plains of the large rivers in Southeast Asia is a prerequisite for the simple removal of As. This study investigated the mechanisms and possibilities for enhancing As removal with naturally occurring Fe in a reliable, low cost and sustainable way. The results of the study show that As removal with Fe is greatly enhanced by the addition of an oxidizing agent (preferably KMnO4 immediately after the pumping of groundwater. Further enhancement of As removal in the presence of Fe can be achieved by adding a small volume of a concentrated basic solution of MnO4- and AlO2-, which has a combined oxidation, coagulation and buffering capacity. Best results were obtained when this solution was mixed with the groundwater immediately after its pumping until a pale pink color appeared. Maximum required reaction time was 10 minutes and subsequent filtration of the water was able to reduce the As concentration to near zero. Concentrations of MnO4- and AlO2- can be varied in the solution to achieve sufficient As removal to suit different Fe/As ratios and the presence of interfering co-occurring anions.

  15. Groundwater modeling of source terms and contaminant plumes for DOE low-level waste performance assessments

    International Nuclear Information System (INIS)

    McDowell-Boyer, L.M.; Wilson, J.E.

    1994-01-01

    Under US Department of Energy (DOE) Order 5820.2A, all sites within the DOE complex must analyze the performance of planned radioactive waste disposal facilities before disposal takes place through the radiological performance assessment process. These assessments consider both exposures to the public from radionuclides potentially released from disposal facilities and protection of groundwater resources. Compliance with requirements for groundwater protection is often the most difficult to demonstrate as these requirements are generally more restrictive than those for other pathways. Modeling of subsurface unsaturated and saturated flow and transport was conducted for two such assessments for the Savannah River site. The computer code PORFLOW was used to evaluate release and transport of radionuclides from different types of disposal unit configurations: vault disposal and trench disposal. The effectiveness of engineered barriers was evaluated in terms of compliance with groundwater protection requirements. The findings suggest that, due to the limited lifetime of engineered barriers, overdesign of facilities for long-lived radionuclides is likely to occur if compliance must be realized for thousands of years

  16. Associating at the European Level: Civil Society Networks in Brussels

    NARCIS (Netherlands)

    Brandsen, T.; Sittermann, B.; Freise, M.; Hallmann, T.

    2014-01-01

    This chapter examines the position of the third sector at the European level, where it has slowly been building a presence. Although great advances have been made, especially from the 1990s onwards, and the sector’s European networks are much stronger than before, it remains institutionally weak and

  17. The Dynamics of network and dyad level supply management

    DEFF Research Database (Denmark)

    Ellegaard, Chris

    -supplier relation and its immediate network context, are presented. In analysing the data, the dynamic interdependency between management of one level and management of the other, will be demonstrated. The analysis reveals a need for an alternating approach to supply management, which takes the dynamic complexity...

  18. Ground-water quality, levels, and flow direction near Fort Cobb Reservoir, Caddo County, Oklahoma, 1998-2000

    Science.gov (United States)

    Becker, Carol J.

    2001-01-01

    Fort Cobb Reservoir in northwest Caddo County Oklahoma is managed by the Bureau of Reclamation for water supply, recreation, flood control, and wildlife. Excessive amounts of nitrogen in the watershed have the potential to cause long-term eutrophication of the reservoir and increase already elevated concentrations of nitrogen in the Rush Springs aquifer. The U.S. Geological Survey in cooperation with the Bureau of Reclamation studied ground water in the area surrounding a swine feeding operation located less than 2 miles upgradient from Fort Cobb Reservoir in Caddo County, Oklahoma. Objectives of the study were to (1) determine if the operation was contributing nitrogen to the ground water and (2) measure changes in ground-water levels and determine the local ground-water flow direction in the area surrounding the swine feeding operation. Nitrate concentrations (28.1 and 31.5 milligrams per liter) were largest in two ground-water samples from a well upgradient of the wastewater lagoon. Nitrate concentrations ranged from 4.30 to 8.20 milligrams per liter in samples from downgradient wells. Traces of ammonia and nitrite were detected in a downgradient well, but not in upgradient wells. d15N values indicate atmospheric nitrogen, synthetic fertilizer, or plants were the predominate sources of nitrate in ground water from the downgradient wells. The d15N values in these samples are depleted in nitrogen-15, indicating that animal waste was not a significant contributor of nitrate. Manganese concentrations (1,150 and 965 micrograms per liter) in samples from a downgradient well were substantially larger than concentrations in samples from other wells, exceeding the secondary drinking-water standard of 50 micrograms per liter. Larger concentrations of bicarbonate, magnesium, fluoride, and iron and a higher pH were also measured in water from a downgradient well. Ground-water levels in an observation well were higher from April to mid-July and lower during the late summer

  19. Study on assessment scenarios of natural phenomena effected on groundwater flow system. Case study for the sea-level change (Contract research)

    International Nuclear Information System (INIS)

    Sakai, Ryutaro; Munakata, Masahiro; Kimura, Hideo

    2009-03-01

    It is important to evaluate effects on the groundwater flow system by the natural phenomena in the safety assessment of geological disposal of radioactive waste. Safety assessment is performed by using safety assessment methods, thus it is necessary to establish reasonable scenarios for safety assessment. In this report, we study change effecting on the groundwater flow system by literature reviews. The scenario of sea level change is expected to have a importance for a safety of disposal facility in coastal area. The recent information related to the groundwater flow condition in sedimentary rocks of sub-seabed coastal area shows that there are four groundwater domains as follows with depth; (1) modern meteoric water, (2) saline water in the transgression period, (3) paleo-fresh water which formed during the last glacial age when sea levels were lower than at present and (4) pre-glacial fossil saline water. This study suggests that the non-current (3) paleo-fresh water at present is possible to move to discharged area at sea floor in the next glacial period by denudation of marine-clay sediments and to become stagnant water again in the next interglacial period by deposition of marine-clay sediments in coastal region. Therefore it is important to predict the scenario considering the denudation and deposition correlated with transgression and regression that could affect the change of groundwater flow velocity, groundwater flow path and groundwater chemical characteristics during the glacial and interglacial period. (author)

  20. Mean-field level analysis of epidemics in directed networks

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jiazeng [School of Mathematical Sciences, Peking University, Beijing 100871 (China); Liu, Zengrong [Mathematics Department, Shanghai University, Shanghai 200444 (China)], E-mail: wangjiazen@yahoo.com.cn, E-mail: zrongliu@online.sh.cn

    2009-09-04

    The susceptible-infected-removed spreading model in a directed graph is studied. The mean-field level rate equations are built with the degree-degree connectivity correlation element and the (in, out)-degree distribution. And the outbreak threshold is obtained analytically-it is determined by the combination of connectivity probability and the degree distribution. Furthermore, the methods of calculating the degree-degree correlations in directed networks are presented. The numerical results of the discrete epidemic processes in networks verify our analyses.

  1. Mean-field level analysis of epidemics in directed networks

    International Nuclear Information System (INIS)

    Wang, Jiazeng; Liu, Zengrong

    2009-01-01

    The susceptible-infected-removed spreading model in a directed graph is studied. The mean-field level rate equations are built with the degree-degree connectivity correlation element and the (in, out)-degree distribution. And the outbreak threshold is obtained analytically-it is determined by the combination of connectivity probability and the degree distribution. Furthermore, the methods of calculating the degree-degree correlations in directed networks are presented. The numerical results of the discrete epidemic processes in networks verify our analyses.

  2. A study on the groundwater flow system for deep geological disposal of high level radioactive waste in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chun Soo; Kim, Kyung Su; Bae, Dae Seok; Park, Byoung Yoon; Koh, Young Kown [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2000-03-01

    The basic framework of groundwater flow is defined as a conceptual 3-D unit of groundwater system based on hydrogeological environments. The fundamental parameters consisting of groundwater system should include topography, geology and climatic conditions. Climatic conditions control the distribution and amounts of groundwater in an interesting study area. The driving forces responsible for groundwater movement are mainly determined by topographic characteristics. The configuration of groundwater system is also controlled by topography. The geological setting and structures control the reservoir size and groundwater flow path. The hydrogeological setting in Korea was classified by primarily topographic characteristics and considered by geological structures and tectonic division. The regional groundwater regime can be grouped into 3 regimes by tectonic setting and four groundwater regions based on an altitude. 35 refs., 9 figs., 21 tabs. (Author)

  3. Optimization of DRASTIC method by artificial neural network, nitrate vulnerability index, and composite DRASTIC models to assess groundwater vulnerability for unconfined aquifer of Shiraz Plain, Iran.

    Science.gov (United States)

    Baghapour, Mohammad Ali; Fadaei Nobandegani, Amir; Talebbeydokhti, Nasser; Bagherzadeh, Somayeh; Nadiri, Ata Allah; Gharekhani, Maryam; Chitsazan, Nima

    2016-01-01

    Extensive human activities and unplanned land uses have put groundwater resources of Shiraz plain at a high risk of nitrate pollution, causing several environmental and human health issues. To address these issues, water resources managers utilize groundwater vulnerability assessment and determination of protection. This study aimed to prepare the vulnerability maps of Shiraz aquifer by using Composite DRASTIC index, Nitrate Vulnerability index, and artificial neural network and also to compare their efficiency. The parameters of the indexes that were employed in this study are: depth to water table, net recharge, aquifer media, soil media, topography, impact of the vadose zone, hydraulic conductivity, and land use. These parameters were rated, weighted, and integrated using GIS, and then, used to develop the risk maps of Shiraz aquifer. The results indicated that the southeastern part of the aquifer was at the highest potential risk. Given the distribution of groundwater nitrate concentrations from the wells in the underlying aquifer, the artificial neural network model offered greater accuracy compared to the other two indexes. The study concluded that the artificial neural network model is an effective model to improve the DRASTIC index and provides a confident estimate of the pollution risk. As intensive agricultural activities are the dominant land use and water table is shallow in the vulnerable zones, optimized irrigation techniques and a lower rate of fertilizers are suggested. The findings of our study could be used as a scientific basis in future for sustainable groundwater management in Shiraz plain.

  4. Long-Term Ground-Water Levels and Transmissivity in the Blackstone River Basin, Northern Rhode Island

    Science.gov (United States)

    Eggleston, Jack R.; Church, Peter E.; Barbaro, Jeffrey R.

    2007-01-01

    Ground water provides about 7.7 million gallons per day, or 28 percent of total water use in the Rhode Island part of the Blackstone River Basin. Primary aquifers in the basin are stratified glacial deposits, composed mostly of sand and gravel along valley bottoms. The ground-water and surface-water system in the Blackstone River Basin is under stress due to population growth, out-of-basin water transfers, industrialization, and changing land-use patterns. Streamflow periodically drops below the Aquatic Base Flow standard, and ground-water withdrawals add to stress on aquatic habitat during low-flow periods. Existing hydrogeologic data were reviewed to examine historical water-level trends and to generate contour maps of water-table altitudes and transmissivity of the sand and gravel aquifer in the Blackstone River Basin in Rhode Island. On the basis of data from four long-term observation wells, water levels appear to have risen slightly in the study area during the past 55 years. Analysis of available data indicates that increased rainfall during the same period is a likely contributor to the water-level rise. Spatial patterns of transmissivity are shown over larger areas and have been refined on the basis of more detailed data coverage as compared to previous mapping studies.

  5. Prediction of long-term influence of ONKALO and Korvensuo reservoir on groundwater level and water balance components on Olkiluoto island

    International Nuclear Information System (INIS)

    Karvonen, T.

    2010-08-01

    The Olkiluoto surface hydrological model was used to compute the influence of various ONKALO leakage scenarios on changes in groundwater level in overburden soils and hydraulic heads in the bedrock. Moreover, the model effect of ONKALO leakages on water balance components of the Olkiluoto Island (runoff, evapotranspiration, discharge to the sea area through the bedrock and discharge from the Korvensuo reservoir) and on the thickness and area of unsaturated bedrock layer were computed. Leakages into ONKALO lower the groundwater level in overburden soils especially during those years when precipitation is smaller than the long-term average value 550 mm a -1 . According to model results groundwater level can be below sea level if leakage rate into ONKALO is 180 l/min or more. If leakage rate is smaller than 180 l/min groundwater level is above sea level all the time also during dry years. The modelling results show that there are local water divides inside the island both on the southern and northern side of ONKALO at all time points and for all leakage rates. The local water divides ensure that sea water cannot intrude to ONKALO via surface waters. A more detailed version of the Olkiluoto surface hydrological model was developed for the area around the infiltration experiment. Site scale data were available for the location of the most transmissive hydrogeological zones. The analysis of hydraulic responses has shown that there are local connections between different areas around the pumping drillhole OL-KR14. The importance of the local responses was verified by an additional small hydrogeological zone HZInf connecting HZ19A, HZ19C, OL-KR14, OL-PP66, OL-PP68 and OL-PP69 that was added to the model. In future studies it is necessary to describe the local zones explicitly in the model to allow more realistic flow simulations. Discharge has been measured manually in four measuring weirs since March 2003. The old V-shaped measuring weirs were replaced by new automatic

  6. Hydrogeochemical assessment of groundwater in Kashmir Valley ...

    Indian Academy of Sciences (India)

    Ravi, occupies an oval shaped depression between two major orogenic axis of ..... tion well network that showed water-level increase due to rapid groundwater ... Other issues such as ecological and social issues need to be taken into account ...

  7. Evaluation of Seasonality in Shallow Groundwater Dynamics and Storage in an Urban Prairie Nature Preserve Using a High-Frequency Sensing Network

    Science.gov (United States)

    Rivera, V. A.; Hernandez-Gonzalez, L. M.; Phillips, C. B.; Nair, A.; Negri, M. C.; Gnaedinger, K. J.; Miller, W. M.; Packman, A. I.

    2017-12-01

    Changing regional climate applies stresses to urban areas in the form of altered weather patterns, requiring new strategies for stormwater runoff management and flood mitigation. At the same time, the proportion of people residing in urban areas is increasing and cities are turning to greenspace as a tool for managing runoff. Gensburg Markham Prairie (GMP), located in Markham, Illinois south of Chicago, is an urban prairie nature preserve and a U.S. National Natural Landmark. Owned by Northeastern Illinois University and managed by the Nature Conservancy, GMP receives runoff from surrounding urban areas and provides valuable stormwater storage, while also hosting high biodiversity and providing critical habitat for sensitive and endemic. A successful management strategy for GMP should preserve both of these valuable ecosystem services. To understand GMP's role within the urban environment, we installed a suite of instruments in 2016 and 2017 to measure surface and groundwater levels, rainfall, soil moisture, and electrical conductivity throughout the prairie. This monitoring network includes 40 sensors collecting high frequency data (every 30 minutes). We are also collecting monthly distributed surface and groundwater samples to quantify a range of anions and cations that signal potentially detrimental anthropogenic impacts on the prairie. In addition, we are using historical and ongoing plant distribution surveys to explore the interactions between spatial patterns in vegetation and water dynamics in the prairie. The high measurement frequency and large diversity of sensor types supports holistic investigation of the response of the prairie to diverse events, including summer thunderstorms, winter road salt runoff, and spring snowmelt. The 18 months of data collected to date reveals clear patterns in response to weather events with influence from soil type and spatial variables. We are using time-series analysis with MODFLOW modelling to explore surface-groundwater

  8. Controlling Voltage Levels of Distribution Network-Radial Feeder after Connecting Wind Turbines to the Network

    Directory of Open Access Journals (Sweden)

    Muhammad Al Badri

    2017-11-01

    Full Text Available Several factors in power generation and supply need to be taken into account such as shortages of energy supply, system stability, and energy quality and system disruption due to network losses, industrial development and population expansion. The addition of wind turbines to the distribution network is of great benefit in providing additional power and solving these problems, but this addition is accompanied by the problem of low voltage network. This research found optimal solutions to the problem of low voltage distribution network after connecting wind turbines. The main idea of this paper is to optimize the low-voltage problem as a result of connecting the wind turbines to the "far end" of the radial feeder for a distribution network and to obtain a voltage level within an acceptable and stable range. The problem of low voltage solved by using the load-drop compensation, capacitor-bank and “doubly-fed” induction generators. The results of this study were based on the operation of the entire design of the simulation system which would be compatible with the reality of the energy flow of all network components by using the PSCAD program. The present analysis program revealed an optimum solution for the low voltage profile of the distribution network after connecting the wind turbine.

  9. Status of groundwater levels and storage volume in the Equus Beds aquifer near Wichita, Kansas, January 2006 to January 2010

    Science.gov (United States)

    Hansen, Cristi V.; Aucott, Walter R.

    2010-01-01

    A part of the Equus Beds aquifer in southwestern Harvey County and northwestern Sedgwick County was developed to supply water to residents of Wichita and for irrigation in south-central Kansas. Groundwater pumping for city and agricultural use caused water levels to decline in a large part of the aquifer northwest of Wichita. In 1965, the city of Wichita began using water from Cheney Reservoir in addition to water from the Equus Beds aquifer to meet the city's increasing demand for water. Irrigation pumpage in the area increased substantially during the 1970s and 1980s and contributed to the water-level declines. Water-level declines reached their maximum to date in October 1992.

  10. Relations between groundwater levels and anthropogenic and meteorological stressors at selected sites in east-central Florida, 1995-2007

    Science.gov (United States)

    Murray, Louis C.

    2010-01-01

    Multivariate linear regression analyses were used to define the relations of water levels in the Upper Floridan aquifer (UFA) and surficial aquifer system (SAS) to anthropogenic and meteorological stressors between 1995 and 2007 at two monitoring well sites (Charlotte Street and Lake Oliver) in east-central Florida. Anthropogenic stressors of interest included municipal and agricultural groundwater withdrawals, and application of reclaimed-water to rapid-infiltration basins (source of aquifer recharge). Meteorological stressors included precipitation and potential evapotranspiration. Overall, anthropogenic and meteorological stressors accounted for about 40 to 89 percent of the variance in UFA and SAS groundwater levels and water-level changes. While mean monthly water levels were better correlated with monthly stressor values, changes in UFA and SAS water levels were better correlated with changes in stressor values. Water levels and water-level changes were influenced by system persistence as the moving-averaged values of both stressor types, which accounted for the influence of the previous month(s) conditions, consistently yielded higher adjusted coefficients of determination (R2 adj) values than did single monthly values. While monthly water-level changes tend to be influenced equally with both stressors across the hydrologically averaged 13-year period, changes were more influenced by one stressor or the other seasonally and during extended wet and dry periods. Seasonally, UFA water-level changes tended to be more influenced by anthropogenic stressors than by meteorological stressors, while changes in SAS water levels tended to be more influenced by meteorological stressors. During extended dry periods (12 months or greater), changes in UFA water levels at Charlotte Street were more affected by anthropogenic stressors than by meteorological stressors, while changes in SAS levels were more affected by meteorological stressors. At Lake Oliver, changes in both

  11. Groundwater levels, geochemistry, and water budget of the Tsala Apopka Lake system, west-central Florida, 2004–12

    Science.gov (United States)

    McBride, W. Scott; Metz, Patricia A.; Ryan, Patrick J.; Fulkerson, Mark; Downing, Harry C.

    2017-12-18

    , and the Upper Floridan aquifer; and to estimate an annual water budget for each pool and for the entire lake system for 2004–12. The hydrologic interactions were evaluated using hydraulic head and geochemical data. Geochemical data, including major ion, isotope, and age-tracer data, were used to evaluate sources of water and to distinguish flow paths. Hydrologic connection of the surficial environment (lakes, ponds, wetlands, and the surficial aquifer) was quantified on the basis of a conceptualized annual water-budget model. The model included the change in surface water and groundwater storage, precipitation, evapotranspiration, surface-water inflow and outflow, and net groundwater exchange with the underlying Upper Floridan aquifer. The control volume for each pool extended to the base of the surficial aquifer and covered an area defined to exceed the maximum inundated area for each pool during 2004–12 by 0.5 foot. Net groundwater flow was computed as a lumped value and was either positive or negative, with a negative value indicating downward or lateral leakage from the control volume and a positive value indicating upward leakage to the control volume.The annual water budget for Tsala Apopka Lake was calculated using a combination of field observations and remotely sensed data for each of three pools and for the composite three pool area. A digital elevation model at a 5-foot grid spacing and bathymetric survey data were used to define the land-surface elevation and volume of each pool and to calculate the changes in inundated area with change in lake stage. Continuous lake-stage and groundwater-level data were used to define the change in storage for each pool. The rainfall data used in the water-budget calculations were based on daily radar reflectance data and measured rainfall from weather stations. Evapotranspiration was computed as a function of reference evapotranspiration, adjusted to actual evapotranspiration using a monthly land-cover coefficient

  12. Using the IRWQIGT Index to Determine Toxicity Levels in Groundwater Resources: A Case Study of Semnan Province

    Directory of Open Access Journals (Sweden)

    Allahbakhsh Javid

    2016-09-01

    Full Text Available The objective of the present descriptive-analytic study was to estimate the toxicity level of the groundwater resources in the Province of Semnan using the IRWQIGT index and its zoning via GIS. The experiments were conducted over the period from October 2013 to October 2014during which time monthly samples were taken from the 41 wells that supply drinking water to the cities and towns in the Province. All the samples were subjected to lab analyses at Semnan Water and Wastewater Laboratory where such chemical parameters as Arsenic, Phenol, Mercury, Detergents, Cadmium, Lead, Chromium, Cyanide, Iron, Magnesium, and TPH were determined according to the procedures of Standard Methods (2008. The measuerments were subsequently used to calculate the groundwater toxicity level index (IRWQIGT. Finally, a zoning map of the IRWQIGT index for Semnan Province was prepared using GIS. Results showed that the IRWQIGT index in Semnan Province ranged between 96.54 and 98.2, indicating an excellent water quality. The lowest (96.585 and highest (98.076 values of IRWQIGT were recorded in the cities of Sorkheh and Mahdishahr, respectively, and that the values for all the parameters were in the standard range. These results indicate that water of excellent quality is available in all the cities in the province so that no toxicity treatment is required.

  13. Development of Tier 1 screening tool for soil and groundwater vulnerability assessment in Korea using classification algorithm in a neural network

    Science.gov (United States)

    Shin, K. H.; Kim, K. H.; Ki, S. J.; Lee, H. G.

    2017-12-01

    The vulnerability assessment tool at a Tier 1 level, although not often used for regulatory purposes, helps establish pollution prevention and management strategies in the areas of potential environmental concern such as soil and ground water. In this study, the Neural Network Pattern Recognition Tool embedded in MATLAB was used to allow the initial screening of soil and groundwater pollution based on data compiled across about 1000 previously contaminated sites in Korea. The input variables included a series of parameters which were tightly related to downward movement of water and contaminants through soil and ground water, whereas multiple classes were assigned to the sum of concentrations of major pollutants detected. Results showed that in accordance with diverse pollution indices for soil and ground water, pollution levels in both media were strongly modulated by site-specific characteristics such as intrinsic soil and other geologic properties, in addition to pollution sources and rainfall. However, classification accuracy was very sensitive to the number of classes defined as well as the types of the variables incorporated, requiring careful selection of input variables and output categories. Therefore, we believe that the proposed methodology is used not only to modify existing pollution indices so that they are more suitable for addressing local vulnerability, but also to develop a unique assessment tool to support decision making based on locally or nationally available data. This study was funded by a grant from the GAIA project(2016000560002), Korea Environmental Industry & Technology Institute, Republic of Korea.

  14. Analysis on the Change in Shallow Groundwater Level based on Monitoring Electric Energy Consumption - A Case Study in the North China Plain

    Science.gov (United States)

    Wang, L.; Wolfgang, K.; Steiner, J. F.

    2016-12-01

    Groundwater has been over-pumped for irrigation in the North China Plain in the past decades causing a drastic decrease in the groundwater level. Shallow groundwater can be recharged by rainfall, and the aquifer could be rehabilitated for sustainable use. However, understanding and maintaining the balance of the aquifer - including climatic as well as anthropogenic influences - are fundamental to enable such a sustainable groundwater management. This is still severely obstructed by a lack of measurements of recharge and exploitation. A project to measure groundwater pumping rate at the distributed scale based on monitoring electric energy consumption is going on in Guantao County (456 km2) located in the southern part of the North China Plain. Considerably less costly than direct measurements of the pumping rate, this approach enables us to (a) cover a larger area and (b) use historic electricity data to reconstruct water use in the past. Pumping tests have been carried out to establish a relation between energy consumption and groundwater exploitation. Based on the results of the pumping tests, the time series of the pumping rate can be estimated from the historical energy consumption and serves as the input for a box model to reconstruct the water balance of the shallow aquifer for recent years. This helps us to determine the relative contribution of recharge due to rainfall as well as drawdown due to groundwater pumping for irrigation. Additionally, 100 electric meters have been installed at the electric transformers supplying power for irrigation. With insights gained from the pumping tests, real-time monitoring of the groundwater exploitation is achieved by converting the measured energy consumption to the water use, and pumping control can also be achieved by limiting the energy use. A monitoring and controlling system can then be set up to implement the strategy of sustainable groundwater use.

  15. Changes between early development (1930–60) and recent (2005–15) groundwater-level altitudes and dissolved-solids and nitrate concentrations In and near Gaines, Terry, and Yoakum Counties, Texas

    Science.gov (United States)

    Thomas, Jonathan V.; Teeple, Andrew; Payne, Jason; Ikard, Scott

    2016-06-21

    Llano Estacado Underground Water Conservation District, Sandy Land Underground Water Conservation District, and South Plains Underground Water Conservation District manage groundwater resources in a part of west Texas near the Texas-New Mexico State line. Declining groundwater levels have raised concerns about the amount of available groundwater in the study area and the potential for water-quality changes resulting from dewatering and increased vertical groundwater movement between adjacent water-bearing units.

  16. Rational Exploitation and Utilizing of Groundwater in Jiangsu Coastal Area

    Science.gov (United States)

    Kang, B.; Lin, X.

    2017-12-01

    Jiangsu coastal area is located in the southeast coast of China, where is a new industrial base and an important coastal and Land Resources Development Zone of China. In the areas with strong human exploitation activities, regional groundwater evolution is obviously affected by human activities. In order to solve the environmental geological problems caused by groundwater exploitation fundamentally, we must find out the forming conditions of regional groundwater hydrodynamic field, and the impact of human activities on groundwater hydrodynamic field evolution and hydrogeochemical evolition. Based on these results, scientific management and reasonable exploitation of the regional groundwater resources can be provided for the utilization. Taking the coastal area of Jiangsu as the research area, we investigate and analyze of the regional hydrogeological conditions. The numerical simulation model of groundwater flow was established according to the water power, chemical and isotopic methods, the conditions of water flow and the influence of hydrodynamic field on the water chemical field. We predict the evolution of regional groundwater dynamics under the influence of human activities and climate change and evaluate the influence of groundwater dynamic field evolution on the environmental geological problems caused by groundwater exploitation under various conditions. We get the following conclusions: Three groundwater exploitation optimal schemes were established. The groundwater salinization was taken as the primary control condition. The substitution model was proposed to model groundwater exploitation and water level changes by BP network method.Then genetic algorithm was used to solve the optimization solution. Three groundwater exploitation optimal schemes were submit to local water resource management. The first sheme was used to solve the groundwater salinization problem. The second sheme focused on dual water supply. The third sheme concerned on emergency water

  17. Geo mathematic tools for the design of a radioisotopes monitoring network in order to modelling the groundwater dynamics processes and hydrodynamic management

    International Nuclear Information System (INIS)

    Peralta, J.L.; Gil, R.; Leyva, D.; Molerio, L.F.; Pin, M.

    2004-01-01

    The present paper, shows the application of geo mathematic tools [Mangin,1981; Molerio,1997] for the design of a radioisotopes monitoring network in order to modelling the groundwater dynamics processes and hydrodynamic management of a Karstic Basin (Almendares-Vento watershed), which is very difficult to evaluate due to the physical-geographical, geologic and hydrogeological characteristics. The Almendares Vento watershed (AVW) is close to the Jaruco-Aguacate watershed, with a similar hydrogeologic and geologic structure, therefore similar result must be expected. In the AVW case is necessary to identify, with more precision, the water propagation limits of the stratified layers according to the waters transit times, recharges and dynamics aquifers, residence time, groundwater contamination and the groundwater-surface water interaction due to the dam placed on the basin. The paper allowed the identification of a monitoring points network, taking into account, between other statistical approaches, the good correlation, the high memory effect, etc. According to the analysis of the variances spectral, have been obtained and optimized the sampling frequency of the network points in the Basin. Besides, it have been identified the necessities to include the detailed evaluation of a specific point of the network in the hydrodynamic study (Vento watershed). In order to evaluate the optimization of the designed monitoring network, the geo mathematic study developed was compared with the results of the mathematical model AQUIMPE, the final result showed the validation of the obtained design. The results of the work allow the best monitoring of the parameters in order to determine the aquifer recharge, residence times, the vulnerability to the waters contamination and the groundwater-surface water interaction

  18. Feasibility analysis of using inverse modeling for estimating natural groundwater recharge from a large-scale soil moisture monitoring network

    Science.gov (United States)

    Wang, Tiejun; Franz, Trenton E.; Yue, Weifeng; Szilagyi, Jozsef; Zlotnik, Vitaly A.; You, Jinsheng; Chen, Xunhong; Shulski, Martha D.; Young, Aaron

    2016-02-01

    Despite the importance of groundwater recharge (GR), its accurate estimation still remains one of the most challenging tasks in the field of hydrology. In this study, with the help of inverse modeling, long-term (6 years) soil moisture data at 34 sites from the Automated Weather Data Network (AWDN) were used to estimate the spatial distribution of GR across Nebraska, USA, where significant spatial variability exists in soil properties and precipitation (P). To ensure the generality of this study and its potential broad applications, data from public domains and literature were used to parameterize the standard Hydrus-1D model. Although observed soil moisture differed significantly across the AWDN sites mainly due to the variations in P and soil properties, the simulations were able to capture the dynamics of observed soil moisture under different climatic and soil conditions. The inferred mean annual GR from the calibrated models varied over three orders of magnitude across the study area. To assess the uncertainties of the approach, estimates of GR and actual evapotranspiration (ETa) from the calibrated models were compared to the GR and ETa obtained from other techniques in the study area (e.g., remote sensing, tracers, and regional water balance). Comparison clearly demonstrated the feasibility of inverse modeling and large-scale (>104 km2) soil moisture monitoring networks for estimating GR. In addition, the model results were used to further examine the impacts of climate and soil on GR. The data showed that both P and soil properties had significant impacts on GR in the study area with coarser soils generating higher GR; however, different relationships between GR and P emerged at the AWDN sites, defined by local climatic and soil conditions. In general, positive correlations existed between annual GR and P for the sites with coarser-textured soils or under wetter climatic conditions. With the rapidly expanding soil moisture monitoring networks around the

  19. Many-objective Groundwater Monitoring Network Design Using Bias-Aware Ensemble Kalman Filtering and Evolutionary Optimization

    Science.gov (United States)

    Kollat, J. B.; Reed, P. M.

    2009-12-01

    This study contributes the ASSIST (Adaptive Strategies for Sampling in Space and Time) framework for improving long-term groundwater monitoring decisions across space and time while accounting for the influences of systematic model errors (or predictive bias). The ASSIST framework combines contaminant flow-and-transport modeling, bias-aware ensemble Kalman filtering (EnKF) and many-objective evolutionary optimization. Our goal in this work is to provide decision makers with a fuller understanding of the information tradeoffs they must confront when performing long-term groundwater monitoring network design. Our many-objective analysis considers up to 6 design objectives simultaneously and consequently synthesizes prior monitoring network design methodologies into a single, flexible framework. This study demonstrates the ASSIST framework using a tracer study conducted within a physical aquifer transport experimental tank located at the University of Vermont. The tank tracer experiment was extensively sampled to provide high resolution estimates of tracer plume behavior. The simulation component of the ASSIST framework consists of stochastic ensemble flow-and-transport predictions using ParFlow coupled with the Lagrangian SLIM transport model. The ParFlow and SLIM ensemble predictions are conditioned with tracer observations using a bias-aware EnKF. The EnKF allows decision makers to enhance plume transport predictions in space and time in the presence of uncertain and biased model predictions by conditioning them on uncertain measurement data. In this initial demonstration, the position and frequency of sampling were optimized to: (i) minimize monitoring cost, (ii) maximize information provided to the EnKF, (iii) minimize failure to detect the tracer, (iv) maximize the detection of tracer flux, (v) minimize error in quantifying tracer mass, and (vi) minimize error in quantifying the moment of the tracer plume. The results demonstrate that the many-objective problem

  20. Descriptions and characterizations of water-level data and groundwater flow for the Brewster Boulevard and Castle Hayne Aquifer Systems and the Tarawa Terrace Aquifer

    Science.gov (United States)

    Faye, Robert E.; Jones, L. Elliott; Suárez-Soto, René J.

    2013-01-01

    This supplement of Chapter A (Supplement 3) summarizes results of analyses of groundwater-level data and describes corresponding elements of groundwater flow such as vertical hydraulic gradients useful for groundwater-flow model calibration. Field data as well as theoretical concepts indicate that potentiometric surfaces within the study area are shown to resemble to a large degree a subdued replica of surface topography. Consequently, precipitation that infiltrates to the water table flows laterally from highland to lowland areas and eventually discharges to streams such as Northeast and Wallace Creeks and New River. Vertically downward hydraulic gradients occur in highland areas resulting in the transfer of groundwater from shallow relatively unconfined aquifers to underlying confined or semi-confined aquifers. Conversely, in the vicinity of large streams such as Wallace and Frenchs Creeks, diffuse upward leakage occurs from underlying confined or semi-confined aquifers. Point water-level data indicating water-table altitudes, water-table altitudes estimated using a regression equation, and estimates of stream levels determined from a digital elevation model (DEM) and topographic maps were used to estimate a predevelopment water-table surface in the study area. Approximate flow lines along hydraulic gradients are shown on a predevelopment potentiometric surface map and extend from highland areas where potentiometric levels are greatest toward streams such as Wallace Creek and Northeast Creek. The distribution of potentiometric levels and corresponding groundwater-flow directions conform closely to related descriptions of the conceptual model.

  1. Hydrogeology, ground-water flow, and tritium movement at low-level radioactive-waste disposal site near Sheffield, Illinois

    Science.gov (United States)

    Garklavs, George; Healy, R.W.

    1986-01-01

    Groundwater flow and tritium movement are described at and near a low-level radioactive waste disposal site near Sheffield, Illinois. Flow in the shallow aquifer is confined to three basins that ultimately drain into a stripmine lake. Most of the flow from the site is through a buried, pebbly sandfilled channel. Remaining flow is toward alluvium of an existing stream. Conceptual flow models for the two largest basins are used to improve definition of flow velocity and direction. Flow velocities range from about 25 to 2,500 ft/yr. Tritium was found in all three basins. The most extensive migration of tritium is coincident with buried channel. Tritium concentrations ranged from detection level to more than 300 nanocuries/L. (USGS)

  2. Geostatistical screening of flood events in the groundwater levels of the diverted inner delta of the Danube River: implications for river bed clogging

    Science.gov (United States)

    Trásy, Balázs; Garamhegyi, Tamás; Laczkó-Dobos, Péter; Kovács, József; Hatvani, István Gábor

    2018-04-01

    The efficient operation of shallow groundwater (SGW) monitoring networks is crucial to water supply, in-land water protection, agriculture and nature conservation. In the present study, the spatial representativity of such a monitoring network in an area that has been thoroughly impacted by anthropogenic activity (river diversion/damming) is assessed, namely the Szigetköz adjacent to the River Danube. The main aims were to assess the spatial representativity of the SGW monitoring network in different discharge scenarios, and investigate the directional characteristics of this representativity, i.e. establish whether geostatistical anisotropy is present, and investigate how this changes with flooding. After the subtraction of a spatial trend from the time series of 85 shallow groundwater monitoring wells tracking flood events from 2006, 2009 and 2013, variography was conducted on the residuals, and the degree of anisotropy was assessed to explore the spatial autocorrelation structure of the network. Since the raw data proved to be insufficient, an interpolated grid was derived, and the final results were scaled to be representative of the original raw data. It was found that during floods the main direction of the spatial variance of the shallow groundwater monitoring wells alters, from perpendicular to the river to parallel with it for over a period of about two week. However, witht the passing of the flood, this returns to its original orientation in 2 months. It is likely that this process is related first to the fast removal of clogged riverbed strata by the flood, then to their slower replacement. In addition, the study highlights the importance of assessing the direction of the spatial autocorrelation structure of shallow groundwater monitoring networks, especially if the aim is to derive interpolated maps for the further investigation or modeling of flow.

  3. Gap Filling of Daily Sea Levels by Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Lyubka Pashova

    2013-06-01

    Full Text Available In the recent years, intelligent methods as artificial neural networks are successfully applied for data analysis from different fields of the geosciences. One of the encountered practical problems is the availability of gaps in the time series that prevent their comprehensive usage for the scientific and practical purposes. The article briefly describes two types of the artificial neural network (ANN architectures - Feed-Forward Backpropagation (FFBP and recurrent Echo state network (ESN. In some cases, the ANN can be used as an alternative on the traditional methods, to fill in missing values in the time series. We have been conducted several experiments to fill the missing values of daily sea levels spanning a 5-years period using both ANN architectures. A multiple linear regression for the same purpose has been also applied. The sea level data are derived from the records of the tide gauge Burgas, which is located on the western Black Sea coast. The achieved results have shown that the performance of ANN models is better than that of the classical one and they are very promising for the real-time interpolation of missing data in the time series.

  4. Viewpoint of defining the groundwater chemistry for the performance assessment on geological disposal of high level radioactive waste

    International Nuclear Information System (INIS)

    Sasamoto, Hiroshi; Yui, Mikazu

    2000-01-01

    This report presents the viewpoint of defining the groundwater chemistry for performance assessment of the second progress report for research and development on geological disposal. Based on the results of statistical analysis (binary scatter plots) of the measured data in addition to the consideration of the first progress report, we defined the five hypothetically modeled groundwaters considering the general geological conditions and importance for performance assessment. In order to evaluate the priority of groundwater chemistries, we have analyzed the above five hypothetical groundwaters by considering the results of multivariate statistical analyses, data reliability, evidence for geochemical controls on groundwater chemistry and exclusion criteria for potential repository sites in Japan. As a result, the fresh reducing high pH (FRHP) type groundwater has been selected for the Reference Case analysis, and the saline reducing high pH (SRHP) type groundwater has been selected for the Alternative Geological Environmental Case analysis, respectively. (author)

  5. Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Executive summary

    International Nuclear Information System (INIS)

    Simmons, C.S.; Cole, C.R.

    1985-05-01

    This document was written to provide guidance to managers and site operators on how ground-water transport codes should be selected for assessing burial site performance. There is a need for a formal approach to selecting appropriate codes from the multitude of potentially useful ground-water transport codes that are currently available. Code selection is a problem that requires more than merely considering mathematical equation-solving methods. These guidelines are very general and flexible and are also meant for developing systems simulation models to be used to assess the environmental safety of low-level waste burial facilities. Code selection is only a single aspect of the overall objective of developing a systems simulation model for a burial site. The guidance given here is mainly directed toward applications-oriented users, but managers and site operators need to be familiar with this information to direct the development of scientifically credible and defensible transport assessment models. Some specific advice for managers and site operators on how to direct a modeling exercise is based on the following five steps: identify specific questions and study objectives; establish costs and schedules for achieving answers; enlist the aid of professional model applications group; decide on approach with applications group and guide code selection; and facilitate the availability of site-specific data. These five steps for managers/site operators are discussed in detail following an explanation of the nine systems model development steps, which are presented first to clarify what code selection entails

  6. Multi-level deep supervised networks for retinal vessel segmentation.

    Science.gov (United States)

    Mo, Juan; Zhang, Lei

    2017-12-01

    Changes in the appearance of retinal blood vessels are an important indicator for various ophthalmologic and cardiovascular diseases, including diabetes, hypertension, arteriosclerosis, and choroidal neovascularization. Vessel segmentation from retinal images is very challenging because of low blood vessel contrast, intricate vessel topology, and the presence of pathologies such as microaneurysms and hemorrhages. To overcome these challenges, we propose a neural network-based method for vessel segmentation. A deep supervised fully convolutional network is developed by leveraging multi-level hierarchical features of the deep networks. To improve the discriminative capability of features in lower layers of the deep network and guide the gradient back propagation to overcome gradient vanishing, deep supervision with auxiliary classifiers is incorporated in some intermediate layers of the network. Moreover, the transferred knowledge learned from other domains is used to alleviate the issue of insufficient medical training data. The proposed approach does not rely on hand-crafted features and needs no problem-specific preprocessing or postprocessing, which reduces the impact of subjective factors. We evaluate the proposed method on three publicly available databases, the DRIVE, STARE, and CHASE_DB1 databases. Extensive experiments demonstrate that our approach achieves better or comparable performance to state-of-the-art methods with a much faster processing speed, making it suitable for real-world clinical applications. The results of cross-training experiments demonstrate its robustness with respect to the training set. The proposed approach segments retinal vessels accurately with a much faster processing speed and can be easily applied to other biomedical segmentation tasks.

  7. F-Area Seepage Basins groundwater monitoring report, fourth quarter 1991 and 1991 summary

    International Nuclear Information System (INIS)

    1992-03-01

    This progress report for fourth quarter 1991 and 1991 summary fro the Savannah River Plant 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

  8. Dual wall reverse circulation drilling with multi-level groundwater sampling for groundwater contaminant plume delineation at Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    International Nuclear Information System (INIS)

    Smuin, D.R.; Morti, E.E.; Zutman, J.L.; Pickering, D.A.

    1995-01-01

    Dual wall reverse circulation (DWRC) drilling was used to drill 48 borings during a groundwater contaminant investigation at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky. This method was selected as an alternative to conventional hollow stem auger drilling for a number of reasons, including the expectation of minimizing waste, increasing the drilling rate, and reducing the potential for cross contamination of aquifers. Groundwater samples were collected from several water-bearing zones during drilling of each borehole. The samples were analyzed for volatile organic compounds using a field gas chromatograph. This approach allowed the investigation to be directed using near-real-time data. Use of downhole geophysical logging, in conjunction with lithologic descriptions of borehole cuttings, resulted in excellent correlation of the geology in the vicinity of the contaminant plume. The total volume of cuttings generated using the DWRC drilling method was less than half of what would have been produced by hollow stem augering; however, the cuttings were recovered in slurry form and had to be dewatered prior to disposal. The drilling rate was very rapid, often approaching 10 ft/min; however, frequent breaks to perform groundwater sampling resulted in an average drilling rate of < 1 ft/min. The time required for groundwater sampling could be shortened by changing the sampling methodology. Analytical results indicated that the drilling method successfully isolated the various water bearing zones and no cross contamination resulted from the investigation

  9. Optimal design of monitoring networks for multiple groundwater quality parameters using a Kalman filter: application to the Irapuato-Valle aquifer.

    Science.gov (United States)

    Júnez-Ferreira, H E; Herrera, G S; González-Hita, L; Cardona, A; Mora-Rodríguez, J

    2016-01-01

    A new method for the optimal design of groundwater quality monitoring networks is introduced in this paper. Various indicator parameters were considered simultaneously and tested for the Irapuato-Valle aquifer in Mexico. The steps followed in the design were (1) establishment of the monitoring network objectives, (2) definition of a groundwater quality conceptual model for the study area, (3) selection of the parameters to be sampled, and (4) selection of a monitoring network by choosing the well positions that minimize the estimate error variance of the selected indicator parameters. Equal weight for each parameter was given to most of the aquifer positions and a higher weight to priority zones. The objective for the monitoring network in the specific application was to obtain a general reconnaissance of the water quality, including water types, water origin, and first indications of contamination. Water quality indicator parameters were chosen in accordance with this objective, and for the selection of the optimal monitoring sites, it was sought to obtain a low-uncertainty estimate of these parameters for the entire aquifer and with more certainty in priority zones. The optimal monitoring network was selected using a combination of geostatistical methods, a Kalman filter and a heuristic optimization method. Results show that when monitoring the 69 locations with higher priority order (the optimal monitoring network), the joint average standard error in the study area for all the groundwater quality parameters was approximately 90 % of the obtained with the 140 available sampling locations (the set of pilot wells). This demonstrates that an optimal design can help to reduce monitoring costs, by avoiding redundancy in data acquisition.

  10. Evaluating data worth for ground-water management under uncertainty

    Science.gov (United States)

    Wagner, B.J.

    1999-01-01

    A decision framework is presented for assessing the value of ground-water sampling within the context of ground-water management under uncertainty. The framework couples two optimization models-a chance-constrained ground-water management model and an integer-programing sampling network design model-to identify optimal pumping and sampling strategies. The methodology consists of four steps: (1) The optimal ground-water management strategy for the present level of model uncertainty is determined using the chance-constrained management model; (2) for a specified data collection budget, the monitoring network design model identifies, prior to data collection, the sampling strategy that will minimize model uncertainty; (3) the optimal ground-water management strategy is recalculated on the basis of the projected model uncertainty after sampling; and (4) the worth of the monitoring strategy is assessed by comparing the value of the sample information-i.e., the projected reduction in management costs-with the cost of data collection. Steps 2-4 are repeated for a series of data collection budgets, producing a suite of management/monitoring alternatives, from which the best alternative can be selected. A hypothetical example demonstrates the methodology's ability to identify the ground-water sampling strategy with greatest net economic benefit for ground-water management.A decision framework is presented for assessing the value of ground-water sampling within the context of ground-water management under uncertainty. The framework couples two optimization models - a chance-constrained ground-water management model and an integer-programming sampling network design model - to identify optimal pumping and sampling strategies. The methodology consists of four steps: (1) The optimal ground-water management strategy for the present level of model uncertainty is determined using the chance-constrained management model; (2) for a specified data collection budget, the monitoring

  11. Prediction of SO{sub 2} levels using neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Belen M. Fernandez de Castro; Jose Manuel Prada Sanchez; Wenceslao Gonzalez Manteiga [and others] [University of Santiago de Compostela, Santiago (Spain). Department of Statistics and Operations Research, Faculty of Mathematics

    2003-05-01

    The paper presents an adaptation of the air pollution control help system in the neighbourhood of a coal-fired power plant in As Pontes (A Coruna, Spain), property of Endesa Generacion S.A., to the European Council Directive 1999/30/CE. This system contains a statistical prediction made half an hour before the measurement, and it helps the staff in the power plant prevent air quality level episodes. The prediction is made using neural network models. This prediction is compared with one made by a semiparametric model. 11 refs., 6 figs., 4 tabs.

  12. Groundwater movement on a Low-lying Carbonate Atoll Island and its Response to Climatic and Sea-level Fluctuations: Roi Namur, Republic of the Marshall Islands

    Science.gov (United States)

    Oberle, F. J.; Swarzenski, P. W.; Storlazzi, C. D.

    2017-12-01

    Atoll islands, most of which only average 1-2 meters above today's sea level, provide a tremendous natural laboratory in which to study and better understand the intensifying impacts of high rates of sea-level rise on tropical reef-lined islands. These islands are unique and on the frontline of negative societal impacts due to their geologic structure and limited water supply. Groundwater resources on atolls are typically minimal due to the low elevation and small surface area of the islands and are also subject to recurring droughts, and more frequent, storm-driven seawater overwash events. Although groundwater is the principal means of freshwater storage on atoll islands and is a major factor in determining the overall sustainability of island settlements, hydrological data on how an aquifer will response to changes in sea-level rise or storm-driven overwash remain limited. Here we present high-resolution time series hydrogeological and geochemical data from a 16 month study to determine the role of an atoll's carbonate geology, land use, and atmospheric and oceanographic forcing in driving coastal groundwater exchange including submarine groundwater discharge on the island of Roi-Namur on Kwajalein Atoll in the Republic of the Marshall Islands. This information can provide new estimates on the recovery and resilience of coastal groundwater resources on similar islands that are expected to experience climate change-driven perturbations.

  13. Evaluation of Elevated Tritium Levels in Groundwater Downgradient from the 618-11 Burial Ground Phase I Investigations

    Energy Technology Data Exchange (ETDEWEB)

    Dresel, P.E.; Smith, R.M.; Williams, B.A.; Thompson, C.J.; Evans, J.C.; Hulstrom, L.C.

    2000-05-01

    This report describes the results of the preliminary investigation of elevated tritium in groundwater discovered near the 618-11 burial ground, located in the eastern part of the Hanford Site. Tritium in one well downgradient of the burial ground was detected at levels up to 8,140,000 pCi/L. The 618-11 burial ground received a variety of radioactive waste from the 300 Area between 1962 and 1967. The burial ground covers 3.5 hectare (8.6 acre) and contains trenches, large diameter caissons, and vertical pipe storage units. The burial ground was stabilized with a native sediment covering. The Energy Northwest reactor complex was constructed immediately east of the burial ground.

  14. Evaluation of Elevated Tritium Levels in Groundwater Downgradient from the 618-11 Burial Ground Phase I Investigations

    International Nuclear Information System (INIS)

    Dresel, P.E.; Smith, R.M.; Williams, B.A.; Thompson, C.J.; Evans, J.C.; Hulstrom, L.C.

    2000-01-01

    This report describes the results of the preliminary investigation of elevated tritium in groundwater discovered near the 618-11 burial ground, located in the eastern part of the Hanford Site. Tritium in one well downgradient of the burial ground was detected at levels up to 8,140,000 pCi/L. The 618-11 burial ground received a variety of radioactive waste from the 300 Area between 1962 and 1967. The burial ground covers 3.5 hectare (8.6 acre) and contains trenches, large diameter caissons, and vertical pipe storage units. The burial ground was stabilized with a native sediment covering. The Energy Northwest reactor complex was constructed immediately east of the burial ground

  15. Bi-decadal groundwater level trends in a semi-arid south indian region: Declines, causes and management

    Directory of Open Access Journals (Sweden)

    Rajendra P. Sishodia

    2016-12-01

    New hydrological insights for the region: Contrary to common perception of widespread groundwater declines only 22–36% of the wells showed statistically significant declines. The use of well depth during dry well periods may slightly underestimate the number of declining wells (by 1% and rate of decline. Increase in groundwater irrigated area combined with rainfall and power subsidy policy, were the main causative factors for the decline. Groundwater decline after implementation of free-electricity policy in 2004 confirmed the nexus between power subsidy and groundwater. These declines are likely to worsen due to future well drillings. Trends in other regions with similar hydro-geologic conditions need to be analyzed to verify groundwater declines and its linkages with power subsidy. Once established, reforms in power subsidy and well permit policy along with conversion to efficient micro–irrigation may be needed to maintain or enhance groundwater availability in the crystalline aquifer region of India (240 million ha.

  16. The role of sediment compaction and groundwater withdrawal in local sea-level rise, Sandy Hook, New Jersey, USA

    Science.gov (United States)

    Johnson, Christopher S.; Miller, Kenneth G.; Browning, James V.; Kopp, Robert E.; Khan, Nicole S.; Fan, Ying; Stanford, Scott D.; Horton, Benjamin P.

    2018-02-01

    The rate of relative sea-level (RSL) rise at Sandy Hook, NJ (4.0 ± 0.5 mm/yr) was higher than The Battery, NY (3.0 ± 0.3 mm/yr) from 1900 to 2012 despite being separated by just 26 km. The difference cannot be explained by differential glacial isostatic adjustment (GIA; 1.4 ± 0.4 and 1.3 ± 0.4 mm/yr RSL rise, respectively) alone. We estimate the contribution of sediment compaction to subsidence at Sandy Hook using high-resolution grain size, percent organic matter, and porosity data from three upper Quaternary (≤13,350 cal yr) cores. The organic matter content (indicates that compaction of deglacial silts likely reduced the column thickness by 10-20% over the past 13,350 cal yrs. While compaction rates were high immediately after the main silt deposition (13,350-13,150 cal yrs BP), rates decreased exponentially after deposition to an average 20th century rate of 0.16 mm/yr (90% Confidence Interval (C.I.), 0.06-0.32 mm/yr). The remaining ∼0.7 mm/yr (90% C.I. 0.3-1.2 mm/yr) difference in subsidence between Sandy Hook and The Battery is likely due to anthropogenic groundwater withdrawal. Historical data from Fort Hancock wells (2 km to the southeast of the Sandy Hook tide gauge) and previous regional work show that local and regional water extraction lowered the water levels in the aquifers underlying Sandy Hook. We suggest that the modern order of contribution to subsidence (highest to lowest) appears to be GIA, local/regional groundwater extraction, and compaction of thick Quaternary silts.

  17. Convolutional Neural Networks for Text Categorization: Shallow Word-level vs. Deep Character-level

    OpenAIRE

    Johnson, Rie; Zhang, Tong

    2016-01-01

    This paper reports the performances of shallow word-level convolutional neural networks (CNN), our earlier work (2015), on the eight datasets with relatively large training data that were used for testing the very deep character-level CNN in Conneau et al. (2016). Our findings are as follows. The shallow word-level CNNs achieve better error rates than the error rates reported in Conneau et al., though the results should be interpreted with some consideration due to the unique pre-processing o...

  18. Ground-water recharge in Fortymile Wash near Yucca Mountain, Nevada, 1992--1993

    International Nuclear Information System (INIS)

    Savard, C.S.

    1994-01-01

    Quantification of the ground-water recharge from streamflow in the Fortymile Wash watershed will contribute to regional ground-water studies. Regional ground-water studies are an important component in the studies evaluating the ground-water flow system as a barrier to the potential migration of radionuclides from the potential underground high-level nuclear waste repository. Knowledge gained in understanding the ground-water recharge mechanisms and pathways in the Pah Canyon area, which is 10 km to the northeast of Yucca Mountain, may transfer to Yucca site specific studies. The current data collection network in Fortymile Canyon does not permit quantification of ground-water recharge, however a qualitative understanding of ground-water recharge was developed from these data

  19. Hydrologic conditions in urban Miami-Dade County, Florida, and the effect of groundwater pumpage and increased sea level on canal leakage and regional groundwater flow

    Science.gov (United States)

    Hughes, Joseph D.; White, Jeremy T.

    2014-01-01

    The extensive and highly managed surface-water system in southeastern Florida constructed during the 20th Century has allowed for the westward expansion of urban and agricultural activities in Miami-Dade County. In urban areas of the county, the surface-water system is used to (1) control urban flooding, (2) supply recharge to production well fields, and (3) control seawater intrusion. Previous studies in Miami-Dade County have determined that on a local scale, leakage from canals adjacent to well fields can supply a large percentage (46 to 78 percent) of the total groundwater pumpage from production well fields. Canals in the urban areas also receive seepage from the Biscayne aquifer that is derived from a combination of local rainfall and groundwater flow from Water Conservation Area 3 and Everglades National Park, which are west of urban areas of Miami-Dade County.

  20. Character-level neural network for biomedical named entity recognition.

    Science.gov (United States)

    Gridach, Mourad

    2017-06-01

    Biomedical named entity recognition (BNER), which extracts important named entities such as genes and proteins, is a challenging task in automated systems that mine knowledge in biomedical texts. The previous state-of-the-art systems required large amounts of task-specific knowledge in the form of feature engineering, lexicons and data pre-processing to achieve high performance. In this paper, we introduce a novel neural network architecture that benefits from both word- and character-level representations automatically, by using a combination of bidirectional long short-term memory (LSTM) and conditional random field (CRF) eliminating the need for most feature engineering tasks. We evaluate our system on two datasets: JNLPBA corpus and the BioCreAtIvE II Gene Mention (GM) corpus. We obtained state-of-the-art performance by outperforming the previous systems. To the best of our knowledge, we are the first to investigate the combination of deep neural networks, CRF, word embeddings and character-level representation in recognizing biomedical named entities. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Integrated Framework for Assessing Impacts of CO₂ Leakage on Groundwater Quality and Monitoring-Network Efficiency: Case Study at a CO₂ Enhanced Oil Recovery Site.

    Science.gov (United States)

    Yang, Changbing; Hovorka, Susan D; Treviño, Ramón H; Delgado-Alonso, Jesus

    2015-07-21

    This study presents a combined use of site characterization, laboratory experiments, single-well push-pull tests (PPTs), and reactive transport modeling to assess potential impacts of CO2 leakage on groundwater quality and leakage-detection ability of a groundwater monitoring network (GMN) in a potable aquifer at a CO2 enhanced oil recovery (CO2 EOR) site. Site characterization indicates that failures of plugged and abandoned wells are possible CO2 leakage pathways. Groundwater chemistry in the shallow aquifer is dominated mainly by silicate mineral weathering, and no CO2 leakage signals have been detected in the shallow aquifer. Results of the laboratory experiments and the field test show no obvious damage to groundwater chemistry should CO2 leakage occur and further were confirmed with a regional-scale reactive transport model (RSRTM) that was built upon the batch experiments and validated with the single-well PPT. Results of the RSRTM indicate that dissolved CO2 as an indicator for CO2 leakage detection works better than dissolved inorganic carbon, pH, and alkalinity at the CO2 EOR site. The detection ability of a GMN was assessed with monitoring efficiency, depending on various factors, including the natural hydraulic gradient, the leakage rate, the number of monitoring wells, the aquifer heterogeneity, and the time for a CO2 plume traveling to the monitoring well.

  2. Meta-modeling of the pesticide fate model MACRO for groundwater exposure assessments using artificial neural networks

    Science.gov (United States)

    Stenemo, Fredrik; Lindahl, Anna M. L.; Gärdenäs, Annemieke; Jarvis, Nicholas

    2007-08-01

    Several simple index methods that use easily accessible data have been developed and included in decision-support systems to estimate pesticide leaching across larger areas. However, these methods often lack important process descriptions (e.g. macropore flow), which brings into question their reliability. Descriptions of macropore flow have been included in simulation models, but these are too complex and demanding for spatial applications. To resolve this dilemma, a neural network simulation meta-model of the dual-permeability macropore flow model MACRO was created for pesticide groundwater exposure assessment. The model was parameterized using pedotransfer functions that require as input the clay and sand content of the topsoil and subsoil, and the topsoil organic carbon content. The meta-model also requires the topsoil pesticide half-life and the soil organic carbon sorption coefficient as input. A fully connected feed-forward multilayer perceptron classification network with two hidden layers, linked to fully connected feed-forward multilayer perceptron neural networks with one hidden layer, trained on sub-sets of the target variable, was shown to be a suitable meta-model for the intended purpose. A Fourier amplitude sensitivity test showed that the model output (the 80th percentile average yearly pesticide concentration at 1 m depth for a 20 year simulation period) was sensitive to all input parameters. The two input parameters related to pesticide characteristics (i.e. soil organic carbon sorption coefficient and topsoil pesticide half-life) were the most influential, but texture in the topsoil was also quite important since it was assumed to control the mass exchange coefficient that regulates the strength of macropore flow. This is in contrast to models based on the advection-dispersion equation where soil texture is relatively unimportant. The use of the meta-model is exemplified with a case-study where the spatial variability of pesticide leaching is

  3. Groundwater-level change and evaluation of simulated water levels for irrigated areas in Lahontan Valley, Churchill County, west-central Nevada, 1992 to 2012

    Science.gov (United States)

    Smith, David W.; Buto, Susan G.; Welborn, Toby L.

    2016-09-14

    The acquisition and transfer of water rights to wetland areas of Lahontan Valley, Nevada, has caused concern over the potential effects on shallow aquifer water levels. In 1992, water levels in Lahontan Valley were measured to construct a water-table map of the shallow aquifer prior to the effects of water-right transfers mandated by the Fallon Paiute-Shoshone Tribal Settlement Act of 1990 (Public Law 101-618, 104 Stat. 3289). From 1992 to 2012, approximately 11,810 water-righted acres, or 34,356 acre-feet of water, were acquired and transferred to wetland areas of Lahontan Valley. This report documents changes in water levels measured during the period of water-right transfers and presents an evaluation of five groundwater-flow model scenarios that simulated water-level changes in Lahontan Valley in response to water-right transfers and a reduction in irrigation season length by 50 percent.Water levels measured in 98 wells from 2012 to 2013 were used to construct a water-table map. Water levels in 73 of the 98 wells were compared with water levels measured in 1992 and used to construct a water-level change map. Water-level changes in the 73 wells ranged from -16.2 to 4.1 feet over the 20-year period. Rises in water levels in Lahontan Valley may correspond to annual changes in available irrigation water, increased canal flows after the exceptionally dry and shortened irrigation season of 1992, and the increased conveyance of water rights transferred to Stillwater National Wildlife Refuge. Water-level declines generally occurred near the boundary of irrigated areas and may be associated with groundwater pumping, water-right transfers, and inactive surface-water storage reservoirs. The largest water-level declines were in the area near Carson Lake.Groundwater-level response to water-right transfers was evaluated by comparing simulated and observed water-level changes for periods representing water-right transfers and a shortened irrigation season in areas near Fallon

  4. Developing a network-level structural capacity index for structural evaluation of pavements.

    Science.gov (United States)

    2013-03-01

    The objective of this project was to develop a structural index for use in network-level pavement evaluation to facilitate : the inclusion of the pavements structural condition in pavement management applications. The primary goal of network-level...

  5. Toward a Theory of Industrial Supply Networks: A Multi-Level Perspective via Network Analysis

    Directory of Open Access Journals (Sweden)

    Yi Zuo

    2017-07-01

    Full Text Available In most supply chains (SCs, transaction relationships between suppliers and customers are commonly considered to be an extrapolation from a linear perspective. However, this traditional linear concept of an SC is egotistic and oversimplified and does not sufficiently reflect the complex and cyclical structure of supplier-customer relationships in current economic and industrial situations. The interactional relationships and topological characteristics between suppliers and customers should be analyzed using supply networks (SNs rather than traditional linear SCs. Therefore, this paper reconceptualizes SCs as SNs in complex adaptive systems (CAS, and presents three main contributions. First, we propose an integrated framework of CAS network by synthesizing multi-level network analysis from the network-, community- and vertex-perspective. The CAS perspective enables us to understand the advances of SN properties. Second, in order to emphasize the CAS properties of SNs, we conducted a real-world SN based on the Japanese industry and describe an advanced investigation of SN theory. The CAS properties help in enriching the SN theory, which can benefit SN management, community economics and industrial resilience. Third, we propose a quantitative metric of entropy to measure the complexity and robustness of SNs. The results not only support a specific understanding of the structural outcomes relevant to SNs, but also deliver efficient and effective support to the management and design of SNs.

  6. Ground-water levels in aquifers used for residential supply, Campton Township, Kane County, Illinois

    Science.gov (United States)

    Kay, Robert T.; Kraske, Kurt A.

    1996-01-01

    The U.S. Geological Survey, in cooperation with the Campton Township Board of Trustees, measured water levels in the aquifers used for residential supply in Campton Township, Kane County, Illinois. Aquifers used for residential supply are the shallow and deep aquifers in the glacial drift, composed of unconsolidated sand and gravels; the Alexandrian-Maquoketa aquifer, composed of dolomite and shale of the Alexandrian Series and the Maquoketa Group; the Galena-Platteville aquifer, composed of dolomite of the Platteville and Galena Groups; and the Ancell aquifer, composed of sandstones of the Glenwood Formation and the St. Peter Sanstone. Water-level altitudes in the shallow drift aquifers generally follow surface topography. Analysis of water-level data does not clearly indicate overutilization of these aquifers. Water-level altitudes in the deep drift aquifers decrease from west to east. Comparison of historical depth to water measurements with current (1995) measurements indicates large decreases in water levels in some areas. The deep drift aquifers may be overutilized at these locations. Water-level altitudes in the Alexandrian-Maquoketa aquifer generally decrease from west to east. The potentiometric surface of the aquifer follows the bedrock-surface topography in some locations. Localized low water-level altitudes and large decreases in water levels indicate the Alexandrian-Maquoketa aquifer is overutilized in several areas. Water-level altitudes in the wells finished in the Galena- Platteville aquifer vary by more than 300 feet. Large decreases in water levels in wells finished in the Galena-Platteville aquifer indicate the Galena-Platteville and Alexandrian-Maquoketa aquifers are overutilized in the northern part of the township. Water-level altitudes in the wells finished in the Ancell aquifer are also highly variable. There is no indication that the Ancell aquifer is overutilized.

  7. High level cognitive information processing in neural networks

    Science.gov (United States)

    Barnden, John A.; Fields, Christopher A.

    1992-01-01

    Two related research efforts were addressed: (1) high-level connectionist cognitive modeling; and (2) local neural circuit modeling. The goals of the first effort were to develop connectionist models of high-level cognitive processes such as problem solving or natural language understanding, and to understand the computational requirements of such models. The goals of the second effort were to develop biologically-realistic model of local neural circuits, and to understand the computational behavior of such models. In keeping with the nature of NASA's Innovative Research Program, all the work conducted under the grant was highly innovative. For instance, the following ideas, all summarized, are contributions to the study of connectionist/neural networks: (1) the temporal-winner-take-all, relative-position encoding, and pattern-similarity association techniques; (2) the importation of logical combinators into connection; (3) the use of analogy-based reasoning as a bridge across the gap between the traditional symbolic paradigm and the connectionist paradigm; and (4) the application of connectionism to the domain of belief representation/reasoning. The work on local neural circuit modeling also departs significantly from the work of related researchers. In particular, its concentration on low-level neural phenomena that could support high-level cognitive processing is unusual within the area of biological local circuit modeling, and also serves to expand the horizons of the artificial neural net field.

  8. Marine water from mid-Holocene sea level highstand trapped in a coastal aquifer: Evidence from groundwater isotopes, and environmental significance

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Stephen [School of Civil, Environmental and Chemical Engineering, RMIT University, Melbourne (Australia); Currell, Matthew, E-mail: Matthew.currell@rmit.edu.au [School of Civil, Environmental and Chemical Engineering, RMIT University, Melbourne (Australia); Cendón, Dioni I. [Australian Nuclear Science and Technology Organisation, Kirrawee (Australia); Connected Water Initiative, School of Biological, Earth and Environmental Sciences, University of New South Wales (UNSW), Sydney (Australia)

    2016-02-15

    A multi-layered coastal aquifer in southeast Australia was assessed using environmental isotopes, to identify the origins of salinity and its links to palaeo-environmental setting. Spatial distribution of groundwater salinity (electrical conductivity values ranging from 0.395 to 56.1 mS/cm) was examined along the coastline along with geological, isotopic and chemical data. This allowed assessment of different salinity sources and emplacement mechanisms. Molar chloride/bromide ratios range from 619 to 1070 (621 to 705 in samples with EC > 15 mS/cm), indicating salts are predominantly marine. Two distinct vertical salinity profiles were observed, one with increasing salinity with depth and another with saline shallow water overlying fresh groundwater. The saline shallow groundwater (EC = 45.4 to 55.7 mS/cm) has somewhat marine-like stable isotope ratios (δ{sup 18}O = − 2.4 to − 1.9 ‰) and radiocarbon activities indicative of middle Holocene emplacement (47.4 to 60.4 pMC). This overlies fresher groundwater with late Pleistocene radiocarbon ages and meteoric stable isotopes (δ{sup 18}O = − 5.5 to − 4.6‰). The configuration suggests surface inundation of the upper sediments by marine water during the mid-Holocene (c. 2–8 kyr BP), when sea level was 1–2 m above today's level. Profiles of chloride, stable isotopes, and radiocarbon indicate mixing between this pre-modern marine water and fresh meteoric groundwater to varying degrees around the coastline. Mixing calculations using chloride and stable isotopes show that in addition to fresh-marine water mixing, some salinity is derived from transpiration by halophytic vegetation (e.g. mangroves). The δ{sup 13}C ratios in saline water (− 17.6 to − 18.4‰) also have vegetation/organic matter signatures, consistent with emplacement by surface inundation and extensive interaction between vegetation and recharging groundwater. Saline shallow groundwater is preserved only in areas where low

  9. Assessing Lake Level Variability and Water Availability in Lake Tana, Ethiopia using a Groundwater Flow Model and GRACE Satellite Data

    Science.gov (United States)

    Hasan, E.; Dokou, Z.; Kirstetter, P. E.; Tarhule, A.; Anagnostou, E. N.; Bagtzoglou, A. C.; Hong, Y.

    2017-12-01

    Lake Tana is the source of the Blue Nile and Ethiopia's largest natural buffer against seasonal variations of rainfall. Assessing the interactions between the lake level fluctuation, hydroclimatic variabilities and anthropogenic factors is essential to detect drought conditions and identify the role of human management in controlling the Lake water balance. Via an extended record of Total Water Storage (TWS) anomalies for the period 1960-2016, a water budget model for the lake water inflow/outflow was developed. Estimates of Lake Level Altimetry (LLA) based on in-situ and satellite altimetry were composited from 1960-2016 and compared to the extended TWS anomalies, the self-calibrated Palmer Drought Severity Index (scPDSI), the El Niño Southern Oscillation (ENSO) and the historical lake water levels and releases. In addition, the simulated lake levels and water budget from a coupled groundwater and lake model of the Lake Tana basin were compared to the above results. Combining the different approaches, the water budget of the lake can be monitored, the drought conditions can be identified and the role of human management in the lake can be determined. For instance, three major drought periods are identified, 1970 to 1977, 1979 to 1987 and 1990 to 1998, each succeeded with an interposed flooding related recovery year, i.e. 1978, 1988 and 1999. The drought/flooding events were attributed mainly to the ENSO interactions that resulted in lake level fluctuations. The period from 2002-2006 was associated with a remarkable decline of the lake level that was attributed partly in drought conditions and the full flow regulation of the Chara Chara weir at the lake outlet, initiated in 2001.

  10. Network-level accident-mapping: Distance based pattern matching using artificial neural network.

    Science.gov (United States)

    Deka, Lipika; Quddus, Mohammed

    2014-04-01

    The objective of an accident-mapping algorithm is to snap traffic accidents onto the correct road segments. Assigning accidents onto the correct segments facilitate to robustly carry out some key analyses in accident research including the identification of accident hot-spots, network-level risk mapping and segment-level accident risk modelling. Existing risk mapping algorithms have some severe limitations: (i) they are not easily 'transferable' as the algorithms are specific to given accident datasets; (ii) they do not perform well in all road-network environments such as in areas of dense road network; and (iii) the methods used do not perform well in addressing inaccuracies inherent in and type of road environment. The purpose of this paper is to develop a new accident mapping algorithm based on the common variables observed in most accident databases (e.g. road name and type, direction of vehicle movement before the accident and recorded accident location). The challenges here are to: (i) develop a method that takes into account uncertainties inherent to the recorded traffic accident data and the underlying digital road network data, (ii) accurately determine the type and proportion of inaccuracies, and (iii) develop a robust algorithm that can be adapted for any accident set and road network of varying complexity. In order to overcome these challenges, a distance based pattern-matching approach is used to identify the correct road segment. This is based on vectors containing feature values that are common in the accident data and the network data. Since each feature does not contribute equally towards the identification of the correct road segments, an ANN approach using the single-layer perceptron is used to assist in "learning" the relative importance of each feature in the distance calculation and hence the correct link identification. The performance of the developed algorithm was evaluated based on a reference accident dataset from the UK confirming that

  11. Excel Spreadsheet Tools for Analyzing Groundwater Level Records and Displaying Information in ArcMap

    Science.gov (United States)

    Tillman, Fred D.

    2009-01-01

    When beginning hydrologic investigations, a first action is often to gather existing sources of well information, compile this information into a single dataset, and visualize this information in a geographic information system (GIS) environment. This report presents tools (macros) developed using Visual Basic for Applications (VBA) for Microsoft Excel 2007 to assist in these tasks. One tool combines multiple datasets into a single worksheet and formats the resulting data for use by the other tools. A second tool produces summary information about the dataset, such as a list of unique site identification numbers, the number of water-level observations for each, and a table of the number of sites with a listed number of water-level observations. A third tool creates subsets of the original dataset based on user-specified options and produces a worksheet with water-level information for each well in the subset, including the average and standard deviation of water-level observations and maximum decline and rise in water levels between any two observations, among other information. This water-level information worksheet can be imported directly into ESRI ArcMap as an 'XY Data' file, and each of the fields of summary well information can be used for custom display. A separate set of VBA tools distributed in an additional Excel workbook creates hydrograph charts of each of the wells in the data subset produced by the aforementioned tools and produces portable document format (PDF) versions of the hydrograph charts. These PDF hydrographs can be hyperlinked to well locations in ArcMap or other GIS applications.

  12. Ground-water discharge determined from measurements of evapotranspiration, other available hydrologic components, and shallow water-level changes, Oasis Valley, Nye County, Nevada

    International Nuclear Information System (INIS)

    Reiner, S.R.; Laczniak, R.J.; DeMeo, G.A.; Smith LaRue, J.; Elliott, P.E.; Nylund, W.E.; Fridrich, C.J.

    2002-01-01

    component of 0.5 foot, is estimated to be about 6,000 acre-feet. Annual subsurface outflow from Oasis Valley into the Amargosa Desert is estimated to be between 30 and 130 acre-feet. Estimates of total annual ground-water withdrawal from Oasis Valley by municipal and non-municipal users in 1996 and 1999 are 440 acre-feet and 210 acre-feet, respectively. Based on these values, natural annual ground-water discharge from Oasis Valley is about 6,100 acre-feet. Total annual discharge was 6,500 acre-feet in 1996 and 6,300 acre-feet in 1999. This quantity of natural ground-water discharge from Oasis Valley exceeds the previous estimate made in 1962 by a factor of about 2.5. Water levels were measured in Oasis Valley to gain additional insight into the ET process. In shallow wells, water levels showed annual fluctuations as large as 7 feet and daily fluctuations as large as 0.2 foot. These fluctuations may be attributed to water loss associated with evapotranspiration. In shallow wells affected by E T, annual minimum depths to water generally occurred in winter or early spring shortly after daily ET reached minimum rates. Annual maximum depths to water generally occurred in late summer or fall shortly after daily ET reached maximum rates. The magnitude of daily water-level fluctuations generally increased as ET increased and decreased as depth to water increased

  13. Natural background levels and threshold values of chemical species in three large-scale groundwater bodies in Northern Italy

    International Nuclear Information System (INIS)

    Molinari, Antonio; Guadagnini, Laura; Marcaccio, Marco; Guadagnini, Alberto

    2012-01-01

    We analyze natural background levels (NBLs) and threshold values (TVs) of spatially distributed chemical species (NH 4 , B and As) which may be a potential pressure and concern in three large scale alluvial and fluvio-deltaic aquifers at different depths of the Apennines and Po river plains in Emilia–Romagna, Northern Italy. Our results are based on statistical methodologies designed to separate the natural and anthropogenic contributions in monitored concentrations by modeling the empirical distribution of the detected concentration with a mixture of probability density functions. Available chemical observations are taken over a 20 years period and are associated with different depths and cover planar investigation scales of the order of hundreds of kilometers. High concentration values detected for NH 4 and B appear to be related to high natural background levels. Due to interaction with the host rock in different geochemical environments we observed that concentration vary in time and space (including in depth) consistently with the hydrogeochemical features and the occurrence of natural attenuation mechanisms in the analyzed reservoirs. Conversely, estimated As NBLs are not consistent with the conceptual model of the hydrogeochemical behavior of the systems analyzed and experimental evidences of As content in aquifer cores. This is due to the inability of these techniques to incorporate the complex dynamics of the processes associated with the specific hydrogeochemical setting. Statistical analyses performed upon aggregating the concentration data according to different time observation windows allow identifying temporal dynamics of NBLs and TVs of target compounds within the observation time frame. Our results highlight the benefit of a dynamic monitoring process and analysis of well demarcated groundwater bodies to update the associated NBLs as a function of the temporal dependence of natural processes occurring in the subsurface. Monitoring protocols could

  14. Natural background levels and threshold values of chemical species in three large-scale groundwater bodies in Northern Italy

    Energy Technology Data Exchange (ETDEWEB)

    Molinari, Antonio, E-mail: ant.molinari2002@libero.it [Politecnico di Milano, Dipartimento di Ingegneria Idraulica, Ambientale, Infrastrutture Viarie e Rilevamento, Piazza L. Da Vinci, 32-20133 Milano (Italy); Guadagnini, Laura [Politecnico di Milano, Dipartimento di Ingegneria Idraulica, Ambientale, Infrastrutture Viarie e Rilevamento, Piazza L. Da Vinci, 32-20133 Milano (Italy); Marcaccio, Marco [ARPA Emilia-Romagna, Direzione Tecnica, Largo Caduti del Lavoro, 6-40122 Bologna (Italy); Guadagnini, Alberto [Politecnico di Milano, Dipartimento di Ingegneria Idraulica, Ambientale, Infrastrutture Viarie e Rilevamento, Piazza L. Da Vinci, 32-20133 Milano (Italy)

    2012-05-15

    We analyze natural background levels (NBLs) and threshold values (TVs) of spatially distributed chemical species (NH{sub 4}, B and As) which may be a potential pressure and concern in three large scale alluvial and fluvio-deltaic aquifers at different depths of the Apennines and Po river plains in Emilia-Romagna, Northern Italy. Our results are based on statistical methodologies designed to separate the natural and anthropogenic contributions in monitored concentrations by modeling the empirical distribution of the detected concentration with a mixture of probability density functions. Available chemical observations are taken over a 20 years period and are associated with different depths and cover planar investigation scales of the order of hundreds of kilometers. High concentration values detected for NH{sub 4} and B appear to be related to high natural background levels. Due to interaction with the host rock in different geochemical environments we observed that concentration vary in time and space (including in depth) consistently with the hydrogeochemical features and the occurrence of natural attenuation mechanisms in the analyzed reservoirs. Conversely, estimated As NBLs are not consistent with the conceptual model of the hydrogeochemical behavior of the systems analyzed and experimental evidences of As content in aquifer cores. This is due to the inability of these techniques to incorporate the complex dynamics of the processes associated with the specific hydrogeochemical setting. Statistical analyses performed upon aggregating the concentration data according to different time observation windows allow identifying temporal dynamics of NBLs and TVs of target compounds within the observation time frame. Our results highlight the benefit of a dynamic monitoring process and analysis of well demarcated groundwater bodies to update the associated NBLs as a function of the temporal dependence of natural processes occurring in the subsurface. Monitoring

  15. Waste and cost reduction using dual wall reverse circulation drilling with multi-level groundwater sampling for contaminant plume delineation

    International Nuclear Information System (INIS)

    Smuin, D.R.

    1995-01-01

    This paper describes the drilling and sampling methods used to delineate a groundwater contaminant plume at the Paducah Gaseous Diffusion Plant (PGDP) during the Groundwater Monitoring IV characterization. The project was unique in that it relied upon dual wall reverse circulation drilling instead of the traditional hollow stem auger method. The Groundwater Monitoring program sought to characterize the boundaries, both vertically and horizontally, of the northeast plume which contains both 99 Tc and trichloroethene. This paper discusses the strengths and weaknesses of the drilling method used by investigators

  16. A review on the impact of embedded generation to network fault level

    Science.gov (United States)

    Yahaya, M. S.; Basar, M. F.; Ibrahim, Z.; Nasir, M. N. N.; Lada, M. Y.; Bukhari, W. M.

    2015-05-01

    The line of Embedded Generation (EG) in power systems especially for renewable energy has increased markedly in recent years. The interconnection of EG has a technical impact which needs to considered. One of the technical challenges faced by the Distribution Network Operator (DNO) is the network fault level. In this paper, the different methods of interconnection with and without EG on the network is analyze by looking at the impact of network fault level. This comparative study made to determine the most effective method to reduce fault level or fault current. This paper will gives basic understanding on the fault level effect when synchronous generator connected to network by different method of interconnection. A three phase fault is introduced at one network bus bar. By employ it to simple network configuration of network configurations which is normal interconnection and splitting network connection with and without EG, the fault level has been simulated and analyzed. Developing the network model by using PSS-Viper™ software package, the fault level for both networks will be showed and the difference is defines. From the review, network splitting was found the best interconnection method and greatest potential for reducing the fault level in the network.

  17. Development of groundwater flow modeling for the low-level radwaste disposal (I)

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Dae Seok; Kim, Chun Soo; Kim, Kyung Soo; Koh, Yong Kweon; Hwang, Yong Soo; Park, Hyun Soo [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-08-01

    Major problems facing in the hydrogeological assessment for a disposal site are resulted from the uncertainties involved in hydraulic parameters of geologic media and the limitation of field investigation methods. These technical problems are, in turn, closely related to the confidence level of numerical modeling results. This research project aims to establish the hydrogeologic assessment methodology suitable to domestic geologic environments with reference to the safety analysis and site characterization for a repository. 26 refs., 65 figs., 14 tabs. (Author)

  18. Convenient telemetry system for precise and continuous measurement of groundwater level and temperature

    Energy Technology Data Exchange (ETDEWEB)

    Tsunakawa, Hideo; Asada, Toshi

    1988-03-25

    A telemeter system has been developed, a device easy to manufacture and install and which facilitates data collection and achieves a relative precision to at least 1 cm in underground water level and 5 m deg C in underground water temperature, thus contributing to earthquake prediction. Its underground water level sensor feeds as voltage the differential pressure of a membrane to which a semiconductor sensor chip is attached. The sensor uses a 12V DC power supply and achieves a sensitivity of 8 mV/cm to sense a 0-5 m water level change as a 1-5 V voltage fluctuation. This sensor is put into a 40 mm-diameter, 100 mm-long brass container and dipped in water at a depth of about 2.5 m. To detect underground water temperature sensor, a semiconductor sensor LM35 is placed in a 25 mm-diameter, 50 mm-long brass container and submerged at a desired depth. The system uses a 12-bit data logger. Telemetry takes place at 1,200 bps via modems and NTT's(Nippon Telegraph and Telecommunications) public telephone line. An example of measurement is shown and mentioned. (2 figs, 5 refs)

  19. Sensor Data Security Level Estimation Scheme for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Alex Ramos

    2015-01-01

    Full Text Available Due to their increasing dissemination, wireless sensor networks (WSNs have become the target of more and more sophisticated attacks, even capable of circumventing both attack detection and prevention mechanisms. This may cause WSN users, who totally trust these security mechanisms, to think that a sensor reading is secure, even when an adversary has corrupted it. For that reason, a scheme capable of estimating the security level (SL that these mechanisms provide to sensor data is needed, so that users can be aware of the actual security state of this data and can make better decisions on its use. However, existing security estimation schemes proposed for WSNs fully ignore detection mechanisms and analyze solely the security provided by prevention mechanisms. In this context, this work presents the sensor data security estimator (SDSE, a new comprehensive security estimation scheme for WSNs. SDSE is designed for estimating the sensor data security level based on security metrics that analyze both attack prevention and detection mechanisms. In order to validate our proposed scheme, we have carried out extensive simulations that show the high accuracy of SDSE estimates.

  20. Sensor Data Security Level Estimation Scheme for Wireless Sensor Networks

    Science.gov (United States)

    Ramos, Alex; Filho, Raimir Holanda

    2015-01-01

    Due to their increasing dissemination, wireless sensor networks (WSNs) have become the target of more and more sophisticated attacks, even capable of circumventing both attack detection and prevention mechanisms. This may cause WSN users, who totally trust these security mechanisms, to think that a sensor reading is secure, even when an adversary has corrupted it. For that reason, a scheme capable of estimating the security level (SL) that these mechanisms provide to sensor data is needed, so that users can be aware of the actual security state of this data and can make better decisions on its use. However, existing security estimation schemes proposed for WSNs fully ignore detection mechanisms and analyze solely the security provided by prevention mechanisms. In this context, this work presents the sensor data security estimator (SDSE), a new comprehensive security estimation scheme for WSNs. SDSE is designed for estimating the sensor data security level based on security metrics that analyze both attack prevention and detection mechanisms. In order to validate our proposed scheme, we have carried out extensive simulations that show the high accuracy of SDSE estimates. PMID:25608215

  1. Sensor data security level estimation scheme for wireless sensor networks.

    Science.gov (United States)

    Ramos, Alex; Filho, Raimir Holanda

    2015-01-19

    Due to their increasing dissemination, wireless sensor networks (WSNs) have become the target of more and more sophisticated attacks, even capable of circumventing both attack detection and prevention mechanisms. This may cause WSN users, who totally trust these security mechanisms, to think that a sensor reading is secure, even when an adversary has corrupted it. For that reason, a scheme capable of estimating the security level (SL) that these mechanisms provide to sensor data is needed, so that users can be aware of the actual security state of this data and can make better decisions on its use. However, existing security estimation schemes proposed for WSNs fully ignore detection mechanisms and analyze solely the security provided by prevention mechanisms. In this context, this work presents the sensor data security estimator (SDSE), a new comprehensive security estimation scheme for WSNs. SDSE is designed for estimating the sensor data security level based on security metrics that analyze both attack prevention and detection mechanisms. In order to validate our proposed scheme, we have carried out extensive simulations that show the high accuracy of SDSE estimates.

  2. A flow level model for wireless multihop ad hoc network throughput

    NARCIS (Netherlands)

    Coenen, Tom Johannes Maria; van den Berg, Hans Leo; Boucherie, Richardus J.

    2005-01-01

    A flow level model for multihop wireless ad hoc networks is presented in this paper. Using a flow level view, we show the main properties and modeling challenges for ad hoc networks. Considering different scenarios, a multihop WLAN and a serial network with a TCP-like flow control protocol, we

  3. Culture, climate change and farm-level groundwater management: An Australian case study

    Science.gov (United States)

    Sanderson, Matthew R.; Curtis, Allen L.

    2016-05-01

    Cultural factors - values, beliefs, and norms - provide important insights into the environmental attitudes, risk perceptions, and behaviors of the general population. Little is known, however, about the ostensibly complex relationships linking those elements of culture to climate change risk perceptions, especially in the context of farm level decision in the ground water context. This paper addresses that gap through an analysis of survey data provided by irrigators in the Namoi catchment of Australia's Murray-Darling Basin. We use Values-Beliefs-Norms theory to construct multivariate models of the relationship between ground water irrigators' interpretations of climate change risks and their implementation of adaptive water conservation practices. Results indicate that these cultural factors are important explanations of irrigators' climate change risk perceptions, and these risk perceptions are related to adaptive ground water management strategies at the farm level. The implications of the findings are discussed for research on the culture-environment nexus and for outreach designed to encourage agricultural adaptations to climate change.

  4. Letter to Editor: RESITA NETWORK - ACADEMIC ENTREPRENEURSHIP AND INNOVATION NETWORK OF SOUTH EASTERN EUROPEAN UNIVERSITIES: AN EXAMPLE OF SUCCESSFUL NETWORKING IN ENTREPRENEURSHIP AND INNOVATION AT ACADEMIC LEVEL

    Directory of Open Access Journals (Sweden)

    Peter Schulte

    2013-05-01

    Full Text Available The foundation, development, activities, and wider social impact of the AcademicEntrepreneurship and Innovation Network of South Eastern European Universities, or shortlyRESITA Network, is presented in this paper as a positive example of successful networking inentrepreneurship and innovation at academic level.

  5. Mitigation of greenhouse gas emissions from reed canary grass in paludiculture: effect of groundwater level

    DEFF Research Database (Denmark)

    Karki, Sandhya; Elsgaard, Lars; Audet, Joachim

    2014-01-01

    below the soil surface. Gross primary production (GPP) was estimated from the above ground biomass yield. Results The mean dry biomass yield across all water table treatments was 6 Mg ha−1 with no significant differences between the treatments. Raising the GWL to the surface decreased both the net...... of peatlands grown with reed canary grass (RCG) and rewetted to various extents. Methods Gas fluxes of CO2, methane (CH4) and nitrous oxide (N2O) were measured with a static chamber technique for 10 months from mesocosms sown with RCG and manipulated to ground water levels (GWL) of 0, −10, −20, −30 and −40 cm...... The results showed that a reduction in total GHG emission can be achieved without losing the productivity of newly established RCG when GWL is maintained close to the surface. Further studies should address the practical constrains and long-term productivity of RCG cultivation in rewetted peatlands....

  6. Evaluation of the fast orthogonal search method for forecasting chloride levels in the Deltona groundwater supply (Florida, USA)

    Science.gov (United States)

    El-Jaat, Majda; Hulley, Michael; Tétreault, Michel

    2018-02-01

    Despite the broad impact and importance of saltwater intrusion in coastal aquifers, little research has been directed towards forecasting saltwater intrusion in areas where the source of saltwater is uncertain. Saline contamination in inland groundwater supplies is a concern for numerous communities in the southern US including the city of Deltona, Florida. Furthermore, conventional numerical tools for forecasting saltwater contamination are heavily dependent on reliable characterization of the physical characteristics of underlying aquifers, information that is often absent or challenging to obtain. To overcome these limitations, a reliable alternative data-driven model for forecasting salinity in a groundwater supply was developed for Deltona using the fast orthogonal search (FOS) method. FOS was applied on monthly water-demand data and corresponding chloride concentrations at water supply wells. Groundwater salinity measurements from Deltona water supply wells were applied to evaluate the forecasting capability and accuracy of the FOS model. Accurate and reliable groundwater salinity forecasting is necessary to support effective and sustainable coastal-water resource planning and management. The available (27) water supply wells for Deltona were randomly split into three test groups for the purposes of FOS model development and performance assessment. Based on four performance indices (RMSE, RSR, NSEC, and R), the FOS model proved to be a reliable and robust forecaster of groundwater salinity. FOS is relatively inexpensive to apply, is not based on rigorous physical characterization of the water supply aquifer, and yields reliable estimates of groundwater salinity in active water supply wells.

  7. Technical and economic evaluation of voltage level in transmission network expansion planning using GA

    International Nuclear Information System (INIS)

    Jalilzadeh, S.; Kazemi, A.; Shayeghi, H.; Madavi, M.

    2008-01-01

    Transmission network expansion planning is an important part of power system planning. Its task is to determine an optimal network configuration according to load growth. It determines where, when and how many new transmission lines should be installed. Up to now, various methods have been presented to solve the static transmission network expansion planning (STNEP) problem, but in all of these methods, the STNEP problem has been solved regardless of voltage level of the lines. In this paper, due to different voltage levels in the transmission network, which cause different annual losses, STNEP has been studied considering the voltage level of the transmission lines and the network loss using the genetic algorithm (GA). Finally, the proposed idea has been examined on Garvers 6 bus network. The results show that considering the loss in a network with different voltage levels decreases the operational costs considerably, and the network satisfies the requirement of delivering electric power more safely and reliably to load centers

  8. Predicting arsenic and heavy metals contamination in groundwater resources of Ghahavand plain based on an artificial neural network optimized by imperialist competitive algorithm

    Directory of Open Access Journals (Sweden)

    Meysam Alizamir

    2017-10-01

    Full Text Available Background: The effects of trace elements on human health and the environment gives importance to the analysis of heavy metals contamination in environmental samples and, more particularly, human food sources. Therefore, the current study aimed to predict arsenic and heavy metals (Cu, Pb, and Zn contamination in the groundwater resources of Ghahavand Plain based on an artificial neural network (ANN optimized by imperialist competitive algorithm (ICA. Methods: This study presents a new method for predicting heavy metal concentrations in the groundwater resources of Ghahavand plain based on ANN and ICA. The developed approaches were trained using 75% of the data to obtain the optimum coefficients and then tested using 25% of the data. Two statistical indicators, the coefficient of determination (R2 and the root-mean-square error (RMSE, were employed to evaluate model performance. A comparison of the performances of the ICA-ANN and ANN models revealed the superiority of the new model. Results of this study demonstrate that heavy metal concentrations can be reliably predicted by applying the new approach. Results: Results from different statistical indicators during the training and validation periods indicate that the best performance can be obtained with the ANN-ICA model. Conclusion: This method can be employed effectively to predict heavy metal concentrations in the groundwater resources of Ghahavand plain.

  9. Hanford groundwater scenario studies

    International Nuclear Information System (INIS)

    Arnett, R.C.; Gephart, R.E.; Deju, R.A.; Cole, C.R.; Ahlstrom, S.W.

    1977-05-01

    This report documents the results of two Hanford groundwater scenario studies. The first study examines the hydrologic impact of increased groundwater recharge resulting from agricultural development in the Cold Creek Valley located west of the Hanford Reservation. The second study involves recovering liquid radioactive waste which has leaked into the groundwater flow system from a hypothetical buried tank containing high-level radioactive waste. The predictive and control capacity of the onsite Hanford modeling technology is used to evaluate both scenarios. The results of the first study indicate that Cold Creek Valley irrigationis unlikely to cause significant changes in the water table underlying the high-level waste areas or in the movement of radionuclides already in the groundwater. The hypothetical tank leak study showed that an active response (in this case waste recovery) can be modeled and is a possible alternative to passive monitoring of radionuclide movement in the unlikely event that high-level waste is introduced into the groundwater

  10. Thermal-hydraulic-geochemical coupled processes around disposed high level nuclear waste in deep granite hosted geological repositories: frontier areas of advanced groundwater research in India

    International Nuclear Information System (INIS)

    Bajpai, R.K.

    2012-01-01

    Indian policy for permanent disposal of high level nuclear wastes with radionuclide having very long half lives include their immobilization in a stable matrix i.e. glasses of suitable composition, its storage in high integrity steel canisters and subsequent disposal in suitable host rock like granites at a depth of 400-500m in stable geological set up. The site for such disposal facilities are selected after vigorous assessment of their stability implying an exhaustive site selection methodology based on a large number of criteria and attributes. In India, an area of about 70000 square kilometers occupied by granites has been subjected to such evaluation for generating comprehensive database on host rock parameters. The sites selected after such intensive analysis are expected to remain immune to processes like seismicity, volcanism, faulting, uplift, erosion, flooding etc. even in distant future spanning over tens of thousands of years. Nevertheless, groundwater has emerged as the only credible pathway through which disposed waste can eventually find its way to accessible biosphere. Hence groundwater research constitutes one of the most important aspects in demonstration of safety of such disposal. The disposed waste due to continuous emission of decay heat creates high temperature field around them with resultant increase in groundwater temperature in the vicinity. Hot groundwater on reacting with steel canisters, backfill clays and cement used around the disposed canister, produces geochemical environment characterized by altered Ph, Eh and groundwater compositions. Acceleration in geochemical interaction among waste-groundwater-clay-cement-granite often results in dissolution or precipitation reactions along the groundwater flow paths i.e. fractures with resultant increase or decrease in their permeability. Thus thermal, hydraulic and geochemical processes work interdependently around the disposed waste. These coupled processes also control the release and

  11. Modeling of Groundwater Resources Heavy Metals Concentration Using Soft Computing Methods: Application of Different Types of Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Meysam Alizamir

    2017-09-01

    Full Text Available Nowadays, groundwater resources play a vital role as a source of drinking water in arid and semiarid regions and forecasting of pollutants content in these resources is very important. Therefore, this study aimed to compare two soft computing methods for modeling Cd, Pb and Zn concentration in groundwater resources of Asadabad Plain, Western Iran. The relative accuracy of several soft computing models, namely multi-layer perceptron (MLP and radial basis function (RBF for forecasting of heavy metals concentration have been investigated. In addition, Levenberg-Marquardt, gradient descent and conjugate gradient training algorithms were utilized for the MLP models. The ANN models for this study were developed using MATLAB R 2014 Software program. The MLP performs better than the other models for heavy metals concentration estimation. The simulation results revealed that MLP model was able to model heavy metals concentration in groundwater resources favorably. It generally is effectively utilized in environmental applications and in the water quality estimations. In addition, out of three algorithms, Levenberg-Marquardt was better than the others were. This study proposed soft computing modeling techniques for the prediction and estimation of heavy metals concentration in groundwater resources of Asadabad Plain. Based on collected data from the plain, MLP and RBF models were developed for each heavy metal. MLP can be utilized effectively in applications of prediction of heavy metals concentration in groundwater resources of Asadabad Plain.

  12. Geostatistics as a tool to improve the natural background level definition: An application in groundwater.

    Science.gov (United States)

    Dalla Libera, Nico; Fabbri, Paolo; Mason, Leonardo; Piccinini, Leonardo; Pola, Marco

    2017-11-15

    The Natural Background Level (NBL), suggested by UE BRIDGE project, is suited for spatially distributed datasets providing a regional value that could be higher than the Threshold Value (TV) set by every country. In hydro-geochemically dis-homogeneous areas, the use of a unique regional NBL, higher than TV, could arise problems to distinguish between natural occurrences and anthropogenic contaminant sources. Hence, the goal of this study is to improve the NBL definition employing a geostatistical approach, which reconstructs the contaminant spatial structure accounting geochemical and hydrogeological relationships. This integrated mapping is fundamental to evaluate the contaminant's distribution impact on the NBL, giving indications to improve it. We decided to test this method on the Drainage Basin of Venice Lagoon (DBVL, NE Italy), where the existing NBL is seven times higher than the TV. This area is notoriously affected by naturally occurring arsenic contamination. An available geochemical dataset collected by 50 piezometers was used to reconstruct the spatial distribution of arsenic in the densely populated area of the DBVL. A cokriging approach was applied exploiting the geochemical relationships among As, Fe and NH4+. The obtained spatial predictions of arsenic concentrations were divided into three different zones: i) areas with an As concentration lower than the TV, ii) areas with an As concentration between the TV and the median of the values higher than the TV, and iii) areas with an As concentration higher than the median. Following the BRIDGE suggestions, where enough samples were available, the 90th percentile for each zone was calculated to obtain a local NBL (LNBL). Differently from the original NBL, this local value gives more detailed water quality information accounting the hydrogeological and geochemical setting, and contaminant spatial variation. Hence, the LNBL could give more indications about the distinction between natural occurrence and

  13. Bit Level Synchronized MAC Protocol for Multireader RFID Networks

    Directory of Open Access Journals (Sweden)

    Namboodiri Vinod

    2010-01-01

    Full Text Available The operation of multiple RFID readers in close proximity results in interference between the readers. This issue is termed the reader collision problem and cannot always be solved by assigning them to different frequency channels due to technical and regulatory limitations. The typical solution is to separate the operation of such readers across time. This sequential operation, however, results in a long delay to identify all tags. We present a bit level synchronized (BLSync MAC protocol for multi-reader RFID networks that allows multiple readers to operate simultaneously on the same frequency channel. The BLSync protocol solves the reader collision problem by allowing all readers to transmit the same query at the same time. We analyze the performance of using the BLSync protocol and demonstrate benefits of 40%–50% in terms of tag reading delay for most settings. The benefits of BLSync, first demonstrated through analysis, are then validated and quantified through simulations on realistic reader-tag layouts.

  14. Declining Groundwater Levels in North India: Understanding Sources of Irrigation Inefficiency

    Science.gov (United States)

    O'Keeffe, J.; Buytaert, W.; Mijic, A.; Brozovic, N.

    2014-12-01

    Over the last half century, the green revolution has transformed India from a famine-prone, drought-susceptible country, into the world's third largest grain producer and one of the most intensely irrigated regions on the planet. This is in no small part due to the country's vast water resources along with an increase in tubewells and more advanced abstraction methods. While agricultural intensification has had undeniable benefits, it has, and continues to have a significant impact on water resources. Unless solutions which take into consideration the ever evolving socio-economic, hydrological and climatic conditions are found, India's agricultural future looks bleak.This research examines the irrigation behaviour of farmers, using data collected during field work in the State of Uttar Pradesh within the Ganges Basin of North India. Significant differences in farmer behaviour and irrigation practices are highlighted, not only between State districts but between individual farmers. This includes the volume of irrigation water applied and the price paid, as well as differences in the yields of crops produced. Analyses of results suggest that this is due to a number of factors, particularly the source of irrigation water. Study areas which had access to cheaper, but crucially less reliable, canal water were found to invest in more efficient water saving technologies in order to reduce the overall cost of irrigation during periods where less expensive canal water is not available. As a result, overall water use and irrigation cost is lower and yields are higher despite very similar climatic conditions. While cheap canal water is not an option for all farmers, the results show that the introduction of more efficient water saving technologies, despite the significant capital expenditure is a viable option for many farmers and costs can be recovered in a relatively short space of time. In addition, the reduction of declining water levels mean that water is abstracted from

  15. Internet Portal For A Distributed Management of Groundwater

    Science.gov (United States)

    Meissner, U. F.; Rueppel, U.; Gutzke, T.; Seewald, G.; Petersen, M.

    The management of groundwater resources for the supply of German cities and sub- urban areas has become a matter of public interest during the last years. Negative headlines in the Rhein-Main-Area dealt with cracks in buildings as well as damaged woodlands and inundated agriculture areas as an effect of varying groundwater levels. Usually a holistic management of groundwater resources is not existent because of the complexity of the geological system, the large number of involved groups and their divergent interests and a lack of essential information. The development of a network- based information system for an efficient groundwater management was the target of the project: ?Grundwasser-Online?[1]. The management of groundwater resources has to take into account various hydro- geological, climatic, water-economical, chemical and biological interrelations [2]. Thus, the traditional approaches in information retrieval, which are characterised by a high personnel and time expenditure, are not sufficient. Furthermore, the efficient control of the groundwater cultivation requires a direct communication between the different water supply companies, the consultant engineers, the scientists, the govern- mental agencies and the public, by using computer networks. The presented groundwater information system consists of different components, especially for the collection, storage, evaluation and visualisation of groundwater- relevant information. Network-based technologies are used [3]. For the collection of time-dependant groundwater-relevant information, modern technologies of Mobile Computing have been analysed in order to provide an integrated approach in the man- agement of large groundwater systems. The aggregated information is stored within a distributed geo-scientific database system which enables a direct integration of simu- lation programs for the evaluation of interactions in groundwater systems. Thus, even a prognosis for the evolution of groundwater states

  16. Surface- and ground-water relations on the Portneuf river, and temporal changes in ground-water levels in the Portneuf Valley, Caribou and Bannock Counties, Idaho, 2001-02

    Science.gov (United States)

    Barton, Gary J.

    2004-01-01

    high flows. Conveyance losses in the Pebble-Topaz reach were greatest, about 283 cubic feet per second, during the spring regulated high flows and were attributed to a hydroelectric project.Comparison of water levels in 30 wells in the Portneuf Valley during September and October 1968 and 2001 indicated long-term declines since 1968; the median decline was 3.4 feet. September and October were selected for characterizing long-term ground-water-level fluctuations because declines associated with irrigation reach a maximum at the end of the irrigation season. The average annual snowpack in the study area has declined significantly; 1945 85 average annual snowpack was 16.1 inches, whereas 1986 through 2002 average annual snowpack was 11.6 inches. Water-level declines during 1998 2002 may be partially attributable to the extended dry climatic conditions. It is unclear whether the declines could be partially attributed to increases in ground-water withdrawals. Between 1968 and 1980, water rights for ground-water withdrawals nearly doubled from 23,500 to 46,000 acre-feet per year. During this period, ground-water levels were relatively constant and did not exhibit a declining trend that could be related to increased ground-water withdrawal rights. However, ground-water withdrawals are not measured in the valley; thus, the amount of water pumped is not known. Since the 1990s, there have been several years when the Chesterfield Reservoir has not completely refilled, and the water in storage behind the reservoir has been depleted by the middle of the irrigation season. In this situation, surface-water diversions for irrigation were terminated before the end of the irrigation season, and irrigators, who were relying in part on diversions from the Portneuf River, had to rely solely on ground water as an alternate supply. Smaller volumes of water in the Chesterfield Reservoir since the 1990s indicate a growing demand for ground-water supplies.

  17. Application of a Coupled Vegetation Competition and Groundwater Simulation Model to Study Effects of Sea Level Rise and Storm Surges on Coastal Vegetation

    Directory of Open Access Journals (Sweden)

    Su Yean Teh

    2015-09-01

    Full Text Available Global climate change poses challenges to areas such as low-lying coastal zones, where sea level rise (SLR and storm-surge overwash events can have long-term effects on vegetation and on soil and groundwater salinities, posing risks of habitat loss critical to native species. An early warning system is urgently needed to predict and prepare for the consequences of these climate-related impacts on both the short-term dynamics of salinity in the soil and groundwater and the long-term effects on vegetation. For this purpose, the U.S. Geological Survey’s spatially explicit model of vegetation community dynamics along coastal salinity gradients (MANHAM is integrated into the USGS groundwater model (SUTRA to create a coupled hydrology–salinity–vegetation model, MANTRA. In MANTRA, the uptake of water by plants is modeled as a fluid mass sink term. Groundwater salinity, water saturation and vegetation biomass determine the water available for plant transpiration. Formulations and assumptions used in the coupled model are presented. MANTRA is calibrated with salinity data and vegetation pattern for a coastal area of Florida Everglades vulnerable to storm surges. A possible regime shift at that site is investigated by simulating the vegetation responses to climate variability and disturbances, including SLR and storm surges based on empirical information.

  18. System-Level Design Methodologies for Networked Multiprocessor Systems-on-Chip

    DEFF Research Database (Denmark)

    Virk, Kashif Munir

    2008-01-01

    is the first such attempt in the published literature. The second part of the thesis deals with the issues related to the development of system-level design methodologies for networked multiprocessor systems-on-chip at various levels of design abstraction with special focus on the modeling and design...... at the system-level. The multiprocessor modeling framework is then extended to include models of networked multiprocessor systems-on-chip which is then employed to model wireless sensor networks both at the sensor node level as well as the wireless network level. In the third and the final part, the thesis...... to the transaction-level model. The thesis, as a whole makes contributions by describing a design methodology for networked multiprocessor embedded systems at three layers of abstraction from system-level through transaction-level to the cycle accurate level as well as demonstrating it practically by implementing...

  19. Water-quality data for the ground-water network in eastern Broward County, Florida, 1983-84

    Science.gov (United States)

    Waller, B.G.; Cannon, F.L.

    1986-01-01

    During 1983-84, groundwater from 63 wells located at 31 sites throughout eastern Broward County, Florida, was sampled and analyzed to determine baseline water quality conditions. The physical and chemical parameters analyzed included field measurements (pH and temperature), physical characteristics (color, turbidity, and specific conductance), major inorganic ions, nutrients, (nitrogen, phosphorus and carbon), selected metals, and total phenolic compounds. Groundwater samples were collected at the end of the dry season (April) and during the wet season (July and September). These data are tabulated, by well, in this report. (USGS)

  20. Groundwater availability of the Mississippi embayment

    Science.gov (United States)

    Clark, Brian R.; Hart, Rheannon M.; Gurdak, Jason J.

    2011-01-01

    Groundwater is an important resource for agricultural and municipal uses in the Mississippi embayment. Arkansas ranks first in the Nation for rice and third for cotton production, with both crops dependent on groundwater as a major source of irrigation requirements. Multiple municipalities rely on the groundwater resources to provide water for industrial and public use, which includes the city of Memphis, Tennessee. The demand for the groundwater resource has resulted in groundwater availability issues in the Mississippi embayment including: (1) declining groundwater levels of 50 feet or more in the Mississippi River Valley alluvial aquifer in parts of eastern Arkansas from agricultural pumping, (2) declining groundwater levels of over 360 feet over the last 90 years in the confined middle Claiborne aquifer in southern Arkansas and northern Louisiana from municipal pumping, and (3) litigation between the State of Mississippi and a Memphis water utility over water rights in the middle Claiborne aquifer. To provide information to stakeholders addressing the groundwater-availability issues, the U.S. Geological Survey Groundwater Resources Program supported a detailed assessment of groundwater availability through the Mississippi Embayment Regional Aquifer Study (MERAS). This assessment included (1) an evaluation of how these resources have changed over time through the use of groundwater budgets, (2) development of a numerical modeling tool to assess system responses to stresses from future human uses and climate trends, and (3) application of statistical tools to evaluate the importance of individual observations within a groundwater-monitoring network. An estimated 12 million acre-feet per year (11 billion gallons per day) of groundwater was pumped in 2005 from aquifers in the Mississippi embayment. Irrigation constitutes the largest groundwater use, accounting for approximately 10 million acre-feet per year (9 billion gallons per day) in 2000 from the Mississippi

  1. Questa baseline and pre-mining ground-water quality investigation. 5. Well installation, water-level data, and surface- and ground-water geochemistry in the Straight Creek drainage basin, Red River Valley, New Mexico, 2001-03

    Science.gov (United States)

    Naus, Cheryl A.; McCleskey, R. Blaine; Nordstrom, D. Kirk; Donohoe, Lisa C.; Hunt, Andrew G.; Paillet, Frederick L.; Morin, Roger H.; Verplanck, Philip L.

    2005-01-01

    The U.S. Geological Survey, in cooperation with the New Mexico Environment Department, is investigating the pre-mining ground-water chemistry at the Molycorp molybdenum mine in the Red River Valley, northern New Mexico. The primary approach is to determine the processes controlling ground-water chemistry at an unmined, off-site, proximal analog. The Straight Creek drainage basin, chosen for this purpose, consists of the same quartz-sericite-pyrite altered andesitic and rhyolitic volcanic rock of Tertiary age as the mine site. The weathered and rugged volcanic bedrock surface is overlain by heterogeneous debris-flow deposits that interfinger with alluvial deposits near the confluence of Straight Creek and the Red River. Pyritized rock in the upper part of the drainage basin is the source of acid rock drainage (pH 2.8-3.3) that infiltrates debris-flow deposits containing acidic ground water (pH 3.0-4.0) and bedrock containing water of circumneutral pH values (5.6-7.7). Eleven observation wells were installed in the Straight Creek drainage basin. The wells were completed in debris-flow deposits, bedrock, and interfingering debris-flow and Red River alluvial deposits. Chemical analyses of ground water from these wells, combined with chemical analyses of surface water, water-level data, and lithologic and geophysical logs, provided information used to develop an understanding of the processes contributing to the chemistry of ground water in the Straight Creek drainage basin. Surface- and ground-water samples were routinely collected for determination of total major cations and selected trace metals; dissolved major cations, selected trace metals, and rare-earth elements; anions and alkalinity; and dissolved-iron species. Rare-earth elements were determined on selected samples only. Samples were collected for determination of dissolved organic carbon, mercury, sulfur isotopic composition (34S and 18O of sulfate), and water isotopic composition (2H and 18O) during

  2. Identification and level of organochlorine insecticide contamination in groundwater and iridology analysis for people in Upper Citarum cascade

    Science.gov (United States)

    Oginawati, K.; Pratama, M. A.

    2016-03-01

    Organochlorines are the main pollutants in the class of persistent organic pollutants which are types of pollutants that are being questioned worldwide due to chronic persistence, toxicity and bioaccumulation. Human around the Citarum River are still using groundwater as a drinking source. It is very risky for people health that consume groundwater because in 2009 the application of organochlorine still found in the Upper Citarum watershed rice field and had potential to contaminate groundwater. Groundwater was analyzed with nine species belonging to the organochlorine pollutants Organic Peristent types. 7 types of organochlorinesAldrin was detected with an average concentration of 0.09 ppb, dieldrin with an average concentration of 24 ppb, heptaklor with an average concentration of 0.51 ppb, with concentrations of endosulfan on average 0.73 ppb, DDT with average concentration of 0.13 ppb, Lindan with an average concentration of 1.2 ppb, endrin with an average concentration of 0.03 ppb. Types with the highest concentration of organochlorine a lindan and endosulfan. Residues of aldrin, dieldrin and heptaklor in groundwater already exceeds the quality standards for drinking water Permenkes 492/2010. Based on the iridology analysis obtained several systems are expected to nervous, immune and reproductive system disorders and toxin deposits under the skin.

  3. Identification and level of organochlorine insecticide contamination in groundwater and iridology analysis for people in Upper Citarum cascade

    International Nuclear Information System (INIS)

    Oginawati, K; Pratama, M A

    2016-01-01

    Organochlorines are the main pollutants in the class of persistent organic pollutants which are types of pollutants that are being questioned worldwide due to chronic persistence, toxicity and bioaccumulation. Human around the Citarum River are still using groundwater as a drinking source. It is very risky for people health that consume groundwater because in 2009 the application of organochlorine still found in the Upper Citarum watershed rice field and had potential to contaminate groundwater. Groundwater was analyzed with nine species belonging to the organochlorine pollutants Organic Peristent types. 7 types of organochlorinesAldrin was detected with an average concentration of 0.09 ppb, dieldrin with an average concentration of 24 ppb, heptaklor with an average concentration of 0.51 ppb, with concentrations of endosulfan on average 0.73 ppb, DDT with average concentration of 0.13 ppb, Lindan with an average concentration of 1.2 ppb, endrin with an average concentration of 0.03 ppb. Types with the highest concentration of organochlorine a lindan and endosulfan. Residues of aldrin, dieldrin and heptaklor in groundwater already exceeds the quality standards for drinking water Permenkes 492/2010. Based on the iridology analysis obtained several systems are expected to nervous, immune and reproductive system disorders and toxin deposits under the skin. (paper)

  4. Fragmenting networks by targeting collective influencers at a mesoscopic level

    Science.gov (United States)

    Kobayashi, Teruyoshi; Masuda, Naoki

    2016-11-01

    A practical approach to protecting networks against epidemic processes such as spreading of infectious diseases, malware, and harmful viral information is to remove some influential nodes beforehand to fragment the network into small components. Because determining the optimal order to remove nodes is a computationally hard problem, various approximate algorithms have been proposed to efficiently fragment networks by sequential node removal. Morone and Makse proposed an algorithm employing the non-backtracking matrix of given networks, which outperforms various existing algorithms. In fact, many empirical networks have community structure, compromising the assumption of local tree-like structure on which the original algorithm is based. We develop an immunization algorithm by synergistically combining the Morone-Makse algorithm and coarse graining of the network in which we regard a community as a supernode. In this way, we aim to identify nodes that connect different communities at a reasonable computational cost. The proposed algorithm works more efficiently than the Morone-Makse and other algorithms on networks with community structure.

  5. Trinets encode tree-child and level-2 phylogenetic networks

    NARCIS (Netherlands)

    L.J.J. van Iersel (Leo); V. Moulton

    2012-01-01

    htmlabstractPhylogenetic networks generalize evolutionary trees, and are commonly used to represent evolutionary histories of species that undergo reticulate evolutionary processes such as hybridization, recombination and lateral gene transfer. Recently, there has been great interest in trying to

  6. Resource Sharing Networks for Higher Education at State Level

    OpenAIRE

    Raman Nair, R.

    1990-01-01

    The project proposal on Development of an Information and Library Network (INFLIBNET) became a public document by 1990. The aim of INFLIBNET as provided in the report was modernizing college and university libraries in India and connecting them through a nation-wide high speed data network using the state-of-art technologies for the optimum utilization of information. INFLIBNET was envisaged to be a major player in promoting scholarly communication among academicians and researchers in India....

  7. Groundwater potential zonation by Remote Sensing and GIS techniques and its relation to the Groundwater level in the Coastal part of the Arani and Koratalai River Basin, Southern India

    Directory of Open Access Journals (Sweden)

    S Suganthi

    2013-07-01

    Full Text Available Groundwater is being pumped extensively from the coastal part of the Arani and Koratalai River Basin, Tamil Nadu, India for irrigation and water supply to the city of Chennai. The objective of this study is to delineate the groundwater potential zones of this area using Remote Sensing (RS and Geographic Information System (GIS techniques. Weighted overlay analysis was used to demarcate the ground- water potential zones. Various thematic layers such as geology, geomorphology, soil, lineament density, drainage density, rainfall and landuse maps were prepared. The geological map was prepared using a Geological Survey of India (GSI district resource map. Indian Remote Sensing System Linear Imaging Self-scanning Sensor III (IRS-1D LISS III satellite imagery was used to prepare the geomorphology, soil, lineament density, drainage density, and landuse maps. The final groundwater potential map was prepared by assigning appropriate weightage to different thematic maps and adding them to the final groundwater potential map. The derived groundwater potential map was overlaid with the groundwater level and location of well fields for validation. The map prepared will help in systematic and proper development of groundwater resources in this area to meet the growing water requirements of the city of Chennai.  Resumen Aguas subterráneas se bombean en gran cantidad desde la parte costera en las cuencas de los ríos Arani, en Tamil Nadu, India, para el riego y el aprovisionamiento de agua a la ciudad de Chennai. El objetivo de este estudio es delinear las zonas potenciales de aguas subterráneas en esta área a través de sistemas de Teledeteción (RS y de Información Geográfica (GIS. Se hizo un análisis sobrepuesto compensado para demarcar las zonas con posibilidad de tener aguas subterráneas. Se prepararon mapas de uso de la tierra con varios elementos temáticos como geología, geomorfología, terreno, densidad de lineamiento, densi- dad de drenaje y

  8. Anomalous Streamflow and Groundwater-Level Changes Before the 1999 M7.6 Chi-Chi Earthquake in Taiwan: Possible Mechanisms

    Science.gov (United States)

    King, Chi-Yu; Chia, Yeeping

    2017-12-01

    Streamflow recorded by a stream gauge located 4 km from the epicenter of the 1999 M7.6 Chi-Chi earthquake in central Taiwan showed a large and rapid anomalous increase of 124 m3/s starting 4 days before the earthquake. This increase was followed by a comparable co-seismic drop to below the background level for 8 months. In addition, groundwater-levels recorded at a well 1.5 km east of the seismogenic fault showed an anomalous rise 2 days before the earthquake, and then a unique 4-cm drop beginning 3 h before the earthquake. The anomalous streamflow increase is attributed to gravity-driven groundwater discharge into the creek through the openings of existing fractures in the steep creek banks crossed by the upstream Shueilikun fault zone, as a result of pre-earthquake crustal buckling. The continued tectonic movement and buckling, together with the downward flow of water in the crust, may have triggered the occurrence of some shallow slow-slip events in the Shueilikun and other nearby fault zones. When these events propagate down-dip to decollement, where the faults merges with the seismogenic Chelungpu fault, they may have triggered other slow-slip events propagating toward the asperity at the hypocenter and the Chelungpu fault. These events may then have caused the observed groundwater-level anomaly and helped to trigger the earthquake.

  9. Conceptual framework and trend analysis of water-level responses to hydrologic stresses, Pahute Mesa–Oasis Valley groundwater basin, Nevada, 1966-2016

    Science.gov (United States)

    Jackson, Tracie R.; Fenelon, Joseph M.

    2018-05-31

    This report identifies water-level trends in wells and provides a conceptual framework that explains the hydrologic stresses and factors causing the trends in the Pahute Mesa–Oasis Valley (PMOV) groundwater basin, southern Nevada. Water levels in 79 wells were analyzed for trends between 1966 and 2016. The magnitude and duration of water-level responses to hydrologic stresses were analyzed graphically, statistically, and with water-level models.The conceptual framework consists of multiple stress-specific conceptual models to explain water-level responses to the following hydrologic stresses: recharge, evapotranspiration, pumping, nuclear testing, and wellbore equilibration. Dominant hydrologic stresses affecting water-level trends in each well were used to categorize trends as nonstatic, transient, or steady state.The conceptual framework of water-level responses to hydrologic stresses and trend analyses provide a comprehensive understanding of the PMOV basin and vicinity. The trend analysis links water-level fluctuations in wells to hydrologic stresses and potential factors causing the trends. Transient and steady-state trend categorizations can be used to determine the appropriate water-level data for groundwater studies.

  10. Usage of link-level performance indicators for HSDPA network-level simulations in E-UMTS

    NARCIS (Netherlands)

    Brouwer, Frank; de Bruin, I.C.C.; Silva, João Carlos; Souto, Nuno; Cercas, Francisco; Correia, Américo

    2004-01-01

    The paper describes integration of HSDPA (high-speed downlink packet access) link-level simulation results into network-level simulations for enhanced UMTS. The link-level simulations model all physical layer features depicted in the 3GPP standards. These include: generation of transport blocks;

  11. Nitrate leaching affected by management options with respect to urine-affected areas and groundwater levels for grazed grassland

    NARCIS (Netherlands)

    Hack-ten Broeke, M.J.D.; Putten, van der A.H.J.

    1997-01-01

    Simulations were performed to quantify the effects of management options on nitrate leaching to the groundwater in grazed pastures. At the experimental farm for sustainable dairy farming ‘De Marke’, experimental data on soil water and nitrates were gathered for two fields during the years 1991–1995.

  12. Perennial filter strips reduce nitrate levels in soil and shallow groundwater after grassland-to-cropland conversion

    Science.gov (United States)

    Xiaobo Zhou; Matthew J. Helmers; Heidi Asbjornsen; Randy Kolka; Mark D. Tomer

    2010-01-01

    Many croplands planted to perennial grasses under the Conservation Reserve Program are being returned to crop production, and with potential consequences for water quality. The objective of this study was to quantify the impact of grassland-to-cropland conversion on nitrate-nitrogen (NO3-N) concentrations in soil and shallow groundwater and to...

  13. Derivation of Threshold Values for Groundwater in Romania, in order to distinguish Point & Diffuse pollution from natural background levels

    NARCIS (Netherlands)

    Schipper, P.N.M.; Radu, E.; Vliegenthart, F.; Balaet, R.

    2010-01-01

    Romania aims to adopt and implement the European Union's legislation, also including that for the field of water management. Like other countries, groundwater in Romania is locally polluted from point sources, such as leaking landfills, as well as from diffuse pollution sources, include fertilizers,

  14. Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Volume 2. Special test cases

    International Nuclear Information System (INIS)

    Simmons, C.S.; Cole, C.R.

    1985-08-01

    This document was written for the National Low-Level Waste Management Program to provide guidance for managers and site operators who need to select ground-water transport codes for assessing shallow-land burial site performance. The guidance given in this report also serves the needs of applications-oriented users who work under the direction of a manager or site operator. The guidelines are published in two volumes designed to support the needs of users having different technical backgrounds. An executive summary, published separately, gives managers and site operators an overview of the main guideline report. Volume 1, titled ''Guideline Approach,'' consists of Chapters 1 through 5 and a glossary. Chapters 2 through 5 provide the more detailed discussions about the code selection approach. This volume, Volume 2, consists of four appendices reporting on the technical evaluation test cases designed to help verify the accuracy of ground-water transport codes. 20 refs

  15. Physical, chemical, and mineralogical data from surficial deposits, groundwater levels, and water composition in the area of Franklin Lake playa and Ash Meadows, California and Nevada

    Science.gov (United States)

    Goldstein, Harland L.; Breit, George N.; Yount, James C.; Reynolds, Richard L.; Reheis, Marith C.; Skipp, Gary L.; Fisher, Eric M.; Lamothe, Paul J.

    2011-01-01

    This report presents data and describes the methods used to determine the physical attributes, as well as the chemical and mineralogical composition of surficial deposits; groundwater levels; and water composition in the area of Franklin Lake playa and Ash Meadows, California and Nevada. The results support studies that examine (1) the interaction between groundwater and the ground surface, and the transport of solutes through the unsaturated zone; (2) the potential for the accumulation of metals and metalloids in surface crusts; (3) emission of dust from metal-rich salt crust; and (4) the effects of metal-rich dusts on human and ecosystem health. The evaporation of shallow (travel as atmospheric dust and affect human and ecosystem health at local to regional scales.

  16. Groundwater level monitoring sampling and analysis plan for environmental monitoring in Waste Area Grouping 6 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-01

    This Sampling and Analysis Plan addresses groundwater level monitoring activities that will be conducted in support of the Environmental Monitoring Plan for Waste Area Grouping (WAG) 6. WAG 6 is a shallow-burial land disposal facility for low-level radioactive waste at the Oak Ridge National Laboratory, a research facility owned by the US Department of Energy and managed by Martin Marietta Energy Systems, Inc. Groundwater level monitoring will be conducted at 129 sites within the WAG. All of the sites will be manually monitored on a semiannual basis. Forty-five of the 128 wells, plus one site in White Oak Lake, will also be equipped with automatic water level monitoring equipment. The 46 sites are divided into three groups. One group will be equipped for continuous monitoring of water level, conductivity, and temperature. The other two groups will be equipped for continuous monitoring of water level only. The equipment will be rotated between the two groups. The data collected from the water level monitoring will be used to support determination of the contaminant flux at WAG 6.

  17. Groundwater level monitoring sampling and analysis plan for environmental monitoring in Waste Area Grouping 6 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1994-04-01

    This Sampling and Analysis Plan addresses groundwater level monitoring activities that will be conducted in support of the Environmental Monitoring Plan for Waste Area Grouping (WAG) 6. WAG 6 is a shallow-burial land disposal facility for low-level radioactive waste at the Oak Ridge National Laboratory, a research facility owned by the US Department of Energy and managed by Martin Marietta Energy Systems, Inc. Groundwater level monitoring will be conducted at 129 sites within the WAG. All of the sites will be manually monitored on a semiannual basis. Forty-five of the 128 wells, plus one site in White Oak Lake, will also be equipped with automatic water level monitoring equipment. The 46 sites are divided into three groups. One group will be equipped for continuous monitoring of water level, conductivity, and temperature. The other two groups will be equipped for continuous monitoring of water level only. The equipment will be rotated between the two groups. The data collected from the water level monitoring will be used to support determination of the contaminant flux at WAG 6

  18. Managing coopetition through horizontal supply chain relations : Linking dyadic and network levels of analysis

    NARCIS (Netherlands)

    Wilhelm, Miriam M.

    2011-01-01

    A growing research stream has expanded the level of analysis beyond single buyer-supplier relations to the network, including supplier-supplier relations. These supplier-supplier relations may constitute a missing link between the traditional analysis of the dyadic and the network level of analysis

  19. Managing coopetition through horizontal supply chain relations : Linking dyadic and network levels of analysis

    NARCIS (Netherlands)

    Wilhelm, Miriam M.

    A growing research stream has expanded the level of analysis beyond single buyer-supplier relations to the network, including supplier-supplier relations. These supplier-supplier relations may constitute a missing link between the traditional analysis of the dyadic and the network level of analysis

  20. Cities, Europeanization and Multi-level Governance: Governing Climate Change through Transnational Municipal Networks

    NARCIS (Netherlands)

    Kern, K.; Bulkeley, H.

    2009-01-01

    This article focuses on a variant of multi-level governance and Europeanization, i.e. the transnational networking of local authorities. Focusing on local climate change policy, the article examines how transnational municipal networks (TMNs) govern in the context of multi-level European governance.

  1. High-resolution monitoring across the soil-groundwater interface - Revealing small-scale hydrochemical patterns with a novel multi-level well

    Science.gov (United States)

    Gassen, Niklas; Griebler, Christian; Stumpp, Christine

    2016-04-01

    Biogeochemical turnover processes in the subsurface are highly variable both in time and space. In order to capture this variability, high resolution monitoring systems are required. Particular in riparian zones the understanding of small-scale biogeochemical processes is of interest, as they are regarded as important buffer zones for nutrients and contaminants with high turnover rates. To date, riparian research has focused on influences of groundwater-surface water interactions on element cycling, but little is known about processes occurring at the interface between the saturated and the unsaturated zone during dynamic flow conditions. Therefore, we developed a new type of high resolution multi-level well (HR-MLW) that has been installed in the riparian zone of the Selke river. This HR-MLW for the first time enables to derive water samples both from the unsaturated and the saturated zone across one vertical profile with a spatial vertical resolution of 0.05 to 0.5 m to a depth of 4 m b.l.s. Water samples from the unsaturated zone are extracted via suction cup sampling. Samples from the saturated zone are withdrawn through glass filters and steel capillaries. Both, ceramic cups and glass filters, are installed along a 1" HDPE piezometer tube. First high resolution hydrochemical profiles revealed a distinct depth-zonation in the riparian alluvial aquifer. A shallow zone beneath the water table carried a signature isotopically and hydrochemically similar to the nearby river, while layers below 1.5 m were influenced by regional groundwater. This zonation showed temporal dynamics related to groundwater table fluctuations and microbial turnover processes. The HR-MLW delivered new insight into mixing and turnover processes between riverwater and groundwater in riparian zones, both in a temporal and spatial dimension. With these new insights, we are able to improve our understanding of dynamic turnover processes at the soil - groundwater interface and of surface

  2. Groundwater-level analysis of selected wells in the Hoosic River Valley near Hoosick Falls, New York, for aquifer framework and properties

    Science.gov (United States)

    Williams, John H.; Heisig, Paul M.

    2018-03-05

    The U.S. Geological Survey, in cooperation with the New York State Department of Environmental Conservation, analyzed groundwater levels, drilling record logs, and field water-quality data from selected wells, and the surficial geology in the Hoosic River valley south of the village of Hoosick Falls, New York, to provide information about the framework and properties of a confined aquifer. The aquifer, which consists of ice-contact sand and gravel overlain by lacustrine clay and silt, was evaluated by the New York State Department of Environmental Conservation as part of their investigation of alternate water supplies for the village whose wellfield has been affected by perfluorooctanoic acid. Wells inventoried in the study area were classified as confined, water table, or transitional between the two aquifer conditions. Groundwater levels in three confined-aquifer wells and a transitional-aquifer well responded to pumping of a test production well finished in the confined aquifer. Groundwater levels in a water-table well showed no detectable water-level change in response to test-well pumping. Analysis of drawdown and recovery data from the three confined-aquifer wells and a transitional-aquifer well through the application of the Theis type-curve method provided estimates of aquifer properties. Representation of a constant-head boundary in the analysis where an unnamed pond and fluvial-terrace deposits abut the valley wall resulted in satisfactory matches of the Theis type curves with the observed water-level responses. Aquifer transmissivity estimates ranged from 1,160 to 1,370 feet squared per day. Aquifer storativity estimates ranged from 5.2×10–5 to 1.1×10–3 and were consistent with the inferred degree of confinement and distance from the represented recharge boundary.

  3. Integrated groundwater data management

    Science.gov (United States)

    Fitch, Peter; Brodaric, Boyan; Stenson, Matt; Booth, Nathaniel; Jakeman, Anthony J.; Barreteau, Olivier; Hunt, Randall J.; Rinaudo, Jean-Daniel; Ross, Andrew

    2016-01-01

    The goal of a data manager is to ensure that data is safely stored, adequately described, discoverable and easily accessible. However, to keep pace with the evolution of groundwater studies in the last decade, the associated data and data management requirements have changed significantly. In particular, there is a growing recognition that management questions cannot be adequately answered by single discipline studies. This has led a push towards the paradigm of integrated modeling, where diverse parts of the hydrological cycle and its human connections are included. This chapter describes groundwater data management practices, and reviews the current state of the art with enterprise groundwater database management systems. It also includes discussion on commonly used data management models, detailing typical data management lifecycles. We discuss the growing use of web services and open standards such as GWML and WaterML2.0 to exchange groundwater information and knowledge, and the need for national data networks. We also discuss cross-jurisdictional interoperability issues, based on our experience sharing groundwater data across the US/Canadian border. Lastly, we present some future trends relating to groundwater data management.

  4. The Meso-level Structure of F/OSS Collaboration Network

    DEFF Research Database (Denmark)

    Conald, Guido; Rullani, Francesco

    2010-01-01

    Social networks in Free/Open Source Software (F/OSS) have been usually analyzed at the level of the single project e.g., [6], or at the level of a whole ecology of projects, e.g., [33]. In this paper, we also investigate the social network generated by developers who collaborate to one or multiple...... F/OSS projects, but we focus on the less-studied meso-level structure emerging when applying to this network a community-detection technique. The network of ‘communities’ emerging from this analysis links sub-groups of densely connected developers, sub-groups that are smaller than the components...... of the network but larger than the teams working on single projects. Our results reveal the complexity of this meso-level structure, where several dense sub-groups of developers are connected by sparse collaboration among different sub-groups. We discuss the theoretical implications of our findings...

  5. Seasonal variations and the influence of geomembrane liners on the levels of PBDEs in landfill leachates, sediment and groundwater in Gauteng Province, South Africa

    Directory of Open Access Journals (Sweden)

    I.V. Sibiya

    2017-06-01

    Full Text Available In the present study, the seasonal concentrations of polybrominated diphenyl ethers (PBDEs in leachate and sediment samples, and the influence of geomembrane liners on PBDE levels and the extent of their infiltration into groundwater on selected landfill sites in Gauteng Province, South Africa were determined. Leachate and sediment samples were collected from seven operational landfill sites namely: Goudkoppies, Robinson Deep, Marie Louis, Soshanguve, Onderstepoort, Hatherly and Garankuwa from Johannesburg and Pretoria, in winter and summer. Groundwater samples were collected from monitoring boreholes from two landfill sites. Liquid-liquid and Soxhlet extraction techniques were employed for the extraction of leachate and groundwater, and sediment respectively using dichloromethane. The extracted samples were subjected to column clean up and, thereafter, analysed using gas chromatography–mass spectroscopy (GC-MS. PBDEs selected for the study were: BDE-17, -28, -47, -100, -99, -153, -154, -183 and -209. The ∑9PBDE concentrations in leachate samples for winter and summer ranged from 0.316–1.36 ng L−1 and 0.560–1.08 ng L−1 respectively. The ∑9 PBDE concentrations obtained for sediment in winter and summer were 3.00–4.91 ng g−1 and 2.50–3.71 ng g−1 respectively. Winter samples exhibited higher (p < 0.05 concentrations for both leachate and sediment samples compared to summer samples. This trend was attributed to high precipitation rate in summer which may have infiltrated into the landfills, subsequently diluting the leachate and sediment samples. In contrast, the winter period is generally dry and PBDEs are, therefore, more likely to be concentrated. The concentrations of PBDEs in leachate and sediment samples were higher in landfill sites with geomembrane liners compared to those without liners. Groundwater samples taken from the vicinity of selected landfill sites without geomembrane liners exhibited high

  6. Technical support to environmental restoration division for groundwater level monitoring effort at entombed Hallam Nuclear Power Facility. Final report, August 1, 1993--July 31, 1993

    International Nuclear Information System (INIS)

    1994-01-01

    This report provides an interim summary of information from a water-level monitoring program. The information was collected by the US Geological Survey (USGS) over a 6-month period. The monitoring program between the US DOE and the USGS was set up to measure water levels in 16 observation wells at the Hallam Nuclear Facility in Hallam, Nebraska. The summary of USGS data includes: (1) a description of the USGS monitoring program; (2) a description of the collection of continuous water-level data; (3) a description of the collection of monthly water-level data; (4) table of observation well number, latitude, longitude, and depth; (5) table of monthly ground-water levels data; (6) table of recorder wells, rainfall, and barometric pressure values; (7) table of recorder well, rainfall, and barometric pressure daily values; and (8) hydrographs of selected wells. 7 figs., 3 tabs

  7. Groundwater monitoring plan for the Hanford Site 200 Area Treated Effluent Disposal Facility

    International Nuclear Information System (INIS)

    DB Barnett

    2000-01-01

    Seven years of groundwater monitoring at the 200 Area Treated Effluent Disposal Facility (TEDF) have shown that the uppermost aquifer beneath the facility is unaffected by TEDF effluent. Effluent discharges have been well below permitted and expected volumes. Groundwater mounding from TEDF operations predicted by various models has not been observed, and waterlevels in TEDF wells have continued declining with the dissipation of the nearby B Pond System groundwater mound. Analytical results for constituents with enforcement limits indicate that concentrations of all these are below Practical Quantitation Limits, and some have produced no detections. Likewise, other constituents on the permit-required list have produced results that are mostly below sitewide background. Comprehensive geochemical analyses of groundwater from TEDF wells has shown that most constituents are below background levels as calculated by two Hanford Site-wide studies. Additionally, major ion proportions and anomalously low tritium activities suggest that groundwater in the aquifer beneath the TEDF has been sequestered from influences of adjoining portions of the aquifer and any discharge activities. This inference is supported by recent hydrogeologic investigations which indicate an extremely slow rate of groundwater movement beneath the TEDF. Detailed evaluation of TEDF-area hydrogeology and groundwater geochemistry indicate that additional points of compliance for groundwater monitoring would be ineffective for this facility, and would produce ambiguous results. Therefore, the current groundwater monitoring well network is retained for continued monitoring. A quarterly frequency of sampling and analysis is continued for all three TEDF wells. The constituents list is refined to include only those parameters key to discerning subtle changes in groundwater chemistry, those useful in detecting general groundwater quality changes from upgradient sources, or those retained for comparison with end

  8. Imaging network level language recovery after left PCA stroke.

    Science.gov (United States)

    Sebastian, Rajani; Long, Charltien; Purcell, Jeremy J; Faria, Andreia V; Lindquist, Martin; Jarso, Samson; Race, David; Davis, Cameron; Posner, Joseph; Wright, Amy; Hillis, Argye E

    2016-05-11

    The neural mechanisms that support aphasia recovery are not yet fully understood. Our goal was to evaluate longitudinal changes in naming recovery in participants with posterior cerebral artery (PCA) stroke using a case-by-case analysis. Using task based and resting state functional magnetic resonance imaging (fMRI) and detailed language testing, we longitudinally studied the recovery of the naming network in four participants with PCA stroke with naming deficits at the acute (0 week), sub acute (3-5 weeks), and chronic time point (5-7 months) post stroke. Behavioral and imaging analyses (task related and resting state functional connectivity) were carried out to elucidate longitudinal changes in naming recovery. Behavioral and imaging analysis revealed that an improvement in naming accuracy from the acute to the chronic stage was reflected by increased connectivity within and between left and right hemisphere "language" regions. One participant who had persistent moderate naming deficit showed weak and decreasing connectivity longitudinally within and between left and right hemisphere language regions. These findings emphasize a network view of aphasia recovery, and show that the degree of inter- and intra- hemispheric balance between the language-specific regions is necessary for optimal recovery of naming, at least in participants with PCA stroke.

  9. Long-term effects of surface coal mining on ground-water levels and quality in two small watersheds in eastern Ohio

    International Nuclear Information System (INIS)

    Cunningham, W.L.; Jones, R.L.

    1990-01-01

    Two small eastern Ohio watersheds surface mined for coal and reclaimed were studied during 1986-89. Water level and water quality data were compared with data from investigations conducted during 1976-83 to determine long-term effects of surface mining on the hydrologic system. Before mining, the watersheds were characterized by flatlying sedimentary rocks above clay beds underlying two major coal seams. Two aquifers overlay each under clay. Surface mining removed the upper aquifer, stripped the coal seam, and replaced the spoil, creating a new aquifer with hydraulic and chemical characteristics different from those of the original upper aquifer. Water levels were measured continuously in one well in each aquifer and every 2 months in other wells. Water levels in upper aquifers reached hydraulic equilibrium from 2 to 5 years after mining and, in middle aquifers, water levels increased more than 5 ft during mining; equilibrium occurred almost immediately thereafter. Water samples were collected from three upper aquifer wells, one middle-aquifer well, a seep from the upper aquifer, and the stream in each watershed. Samples were collected in 1986, 1987, 1988, and 1989. In both watersheds, sulfate replaced bicarbonate as the dominant anion in the upper aquifer after mining. In general, significant increases in concentrations of dissolved constituents in groundwater resulted from surface mining. The continued decrease in pH indicates that groundwater had not reached complete geochemical equilibrium in either watershed more than 8 years after mining ended

  10. Radionuclide migration in groundwater at a low-level waste disposal site: a comparison of predictive performance modeling versus field observations

    International Nuclear Information System (INIS)

    Robertson, D.E.; Myers, D.A.; Bergeron, M.P.; Champ, D.R.; Killey, R.W.D.; Moltyaner, G.L.; Young, J.L.

    1985-08-01

    This paper describes a project which is structured to test the concept of modeling a shallow land low-level waste burial site. The project involves a comparison of the actual observed radionuclide migration in groundwaters at a 30-year-old well-monitored field site with the results of predictive transport modeling. The comparison is being conducted as a cooperative program with the Atomic Energy of Canada Ltd. (AECL) at the low-level waste management area at the Chalk River Nuclear Laboratories, Ontario, Canada. A joint PNL-AECL field inviestigation was conducted in 1983 and 1984 to complement the existing extensive data base on actual radionuclide migration. Predictive transport modeling is currently being conducted for this site; first, as if it were a new location being considered for a low-level waste shallow-land burial site and only minimal information about the site were available, and second, utilizing the extensive data base available for the site. The modeling results will then be compared with the empirical observations to provide insight into the level of effort needed to reasonably predict the spacial and temporal movement of radionuclides in the groundwater enviroment. 8 refs., 5 figs.,

  11. Radionuclide migration in groundwater at a low-level waste disposal site: a comparison of predictive performance modeling versus field observations

    International Nuclear Information System (INIS)

    Robertson, D.E.; Myers, D.A.; Abel, K.H.; Bergeron, M.P.; Champ, D.R.; Killey, R.W.D.; Moltyaner, G.L.; Young, J.L.

    1986-01-01

    This paper describes a project which is structured to test the concept of modeling a shallow land low-level waste burial site. The project involves a comparison of the actual observed radionuclide migration in groundwaters at a 30-year old well-monitored field site with the results of predictive transport modeling. The comparison is being conducted as a cooperative program with the Atomic Energy of Canada Ltd. (AECL) at the low-level waste management area at the Chalk River Nuclear Laboratories, Ontario, Canada. A joint PNL-AECL field investigation was conducted in 1983 and 1984 to compliment the existing extensive data base on actual radionuclide migration. Predictive transport modeling is currently being conducted for this site; first, as if it were a new location being considered for a low-level waste shallow-land burial site and only minimal information about the site were available, and second, utilizing the extensive data base available for the site. The modeling results will then be compared with the level of effort needed to reasonably predict the spacial and temporal movement of radionuclides in the groundwater environment

  12. Quantifying Urban Groundwater in Environmental Field Observatories

    Science.gov (United States)

    Welty, C.; Miller, A. J.; Belt, K.; Smith, J. A.; Band, L. E.; Groffman, P.; Scanlon, T.; Warner, J.; Ryan, R. J.; Yeskis, D.; McGuire, M. P.

    2006-12-01

    Despite the growing footprint of urban landscapes and their impacts on hydrologic and biogeochemical cycles, comprehensive field studies of urban water budgets are few. The cumulative effects of urban infrastructure (buildings, roads, culverts, storm drains, detention ponds, leaking water supply and wastewater pipe networks) on temporal and spatial patterns of groundwater stores, fluxes, and flowpaths are poorly understood. The goal of this project is to develop expertise and analytical tools for urban groundwater systems that will inform future environmental observatory planning and that can be shared with research teams working in urban environments elsewhere. The work plan for this project draws on a robust set of information resources in Maryland provided by ongoing monitoring efforts of the Baltimore Ecosystem Study (BES), USGS, and the U.S. Forest Service working together with university scientists and engineers from multiple institutions. A key concern is to bridge the gap between small-scale intensive field studies and larger-scale and longer-term hydrologic patterns using synoptic field surveys, remote sensing, numerical modeling, data mining and visualization tools. Using the urban water budget as a unifying theme, we are working toward estimating the various elements of the budget in order to quantify the influence of urban infrastructure on groundwater. Efforts include: (1) comparison of base flow behavior from stream gauges in a nested set of watersheds at four different spatial scales from 0.8 to 171 km2, with diverse patterns of impervious cover and urban infrastructure; (2) synoptic survey of well water levels to characterize the regional water table; (3) use of airborne thermal infrared imagery to identify locations of groundwater seepage into streams across a range of urban development patterns; (4) use of seepage transects and tracer tests to quantify the spatial pattern of groundwater fluxes to the drainage network in selected subwatersheds; (5

  13. Critical network effect induces business oscillations in multi-level marketing systems

    OpenAIRE

    Juanico, Dranreb Earl

    2012-01-01

    The "social-networking revolution" of late (e.g., with the advent of social media, Facebook, and the like) has been propelling the crusade to elucidate the embedded networks that underlie economic activity. An unexampled synthesis of network science and economics uncovers how the web of human interactions spurred by familiarity and similarity could potentially induce the ups and downs ever so common to our economy. Zeroing in on the million-strong global industry known as multi-level marketin...

  14. Information Extraction with Character-level Neural Networks and Free Noisy Supervision

    OpenAIRE

    Meerkamp, Philipp; Zhou, Zhengyi

    2016-01-01

    We present an architecture for information extraction from text that augments an existing parser with a character-level neural network. The network is trained using a measure of consistency of extracted data with existing databases as a form of noisy supervision. Our architecture combines the ability of constraint-based information extraction systems to easily incorporate domain knowledge and constraints with the ability of deep neural networks to leverage large amounts of data to learn compl...

  15. Quality-assurance plan for groundwater activities, U.S. Geological Survey, Washington Water Science Center

    Science.gov (United States)

    Kozar, Mark D.; Kahle, Sue C.

    2013-01-01

    This report documents the standard procedures, policies, and field methods used by the U.S. Geological Survey’s (USGS) Washington Water Science Center staff for activities related to the collection, processing, analysis, storage, and publication of groundwater data. This groundwater quality-assurance plan changes through time to accommodate new methods and requirements developed by the Washington Water Science Center and the USGS Office of Groundwater. The plan is based largely on requirements and guidelines provided by the USGS Office of Groundwater, or the USGS Water Mission Area. Regular updates to this plan represent an integral part of the quality-assurance process. Because numerous policy memoranda have been issued by the Office of Groundwater since the previous groundwater quality assurance plan was written, this report is a substantial revision of the previous report, supplants it, and contains significant additional policies not covered in the previous report. This updated plan includes information related to the organization and responsibilities of USGS Washington Water Science Center staff, training, safety, project proposal development, project review procedures, data collection activities, data processing activities, report review procedures, and archiving of field data and interpretative information pertaining to groundwater flow models, borehole aquifer tests, and aquifer tests. Important updates from the previous groundwater quality assurance plan include: (1) procedures for documenting and archiving of groundwater flow models; (2) revisions to procedures and policies for the creation of sites in the Groundwater Site Inventory database; (3) adoption of new water-level forms to be used within the USGS Washington Water Science Center; (4) procedures for future creation of borehole geophysics, surface geophysics, and aquifer-test archives; and (5) use of the USGS Multi Optional Network Key Entry System software for entry of routine water-level data

  16. Evaluation of levels of antibiotic resistance in groundwater-derived E. coli isolates in the Midwest of Ireland and elucidation of potential predictors of resistance

    Science.gov (United States)

    O'Dwyer, Jean; Hynds, Paul; Pot, Matthieu; Adley, Catherine C.; Ryan, Michael P.

    2017-06-01

    Antibiotic-resistant (pathogenic and non-pathogenic) organisms and genes are now acknowledged as significant emerging aquatic contaminants with potentially adverse human and ecological health impacts, and thus require monitoring. This study is the first to investigate levels of resistance among Irish groundwater (private wells) samples; Escherichia coli isolates were examined against a panel of commonly prescribed human and veterinary therapeutic antibiotics, followed by determination of the causative factors of resistance. Overall, 42 confirmed E. coli isolates were recovered from a groundwater-sampling cohort. Resistance to the human panel of antibiotics was moderate; nine (21.4%) E. coli isolates demonstrated resistance to one or more human antibiotics. Conversely, extremely high levels of resistance to veterinary antibiotics were found, with all isolates presenting resistance to one or more veterinary antibiotics. Particularly high levels of resistance (93%) were found with respect to the aminoglycoside class of antibiotics. Results of statistical analysis indicate a significant association between the presence of human (multiple) antibiotic resistance ( p = 0.002-0.011) and both septic tank density and the presence of vulnerable sub-populations (<5 years). For the veterinary antibiotics, results point to a significant relationship ( p = <0.001) between livestock (cattle) density and the prevalence of multiple antibiotic resistant E. coli. Groundwater continues to be an important resource in Ireland, particularly in rural areas; thus, results of this preliminary study offer a valuable insight into the prevalence of antibiotic resistance in the hydrogeological environment and establish a need for further research with a larger geological diversity.

  17. Compliance Groundwater Monitoring of Nonpoint Sources - Emerging Approaches

    Science.gov (United States)

    Harter, T.

    2008-12-01

    Groundwater monitoring networks are typically designed for regulatory compliance of discharges from industrial sites. There, the quality of first encountered (shallow-most) groundwater is of key importance. Network design criteria have been developed for purposes of determining whether an actual or potential, permitted or incidental waste discharge has had or will have a degrading effect on groundwater quality. The fundamental underlying paradigm is that such discharge (if it occurs) will form a distinct contamination plume. Networks that guide (post-contamination) mitigation efforts are designed to capture the shape and dynamics of existing, finite-scale plumes. In general, these networks extend over areas less than one to ten hectare. In recent years, regulatory programs such as the EU Nitrate Directive and the U.S. Clean Water Act have forced regulatory agencies to also control groundwater contamination from non-incidental, recharging, non-point sources, particularly agricultural sources (fertilizer, pesticides, animal waste application, biosolids application). Sources and contamination from these sources can stretch over several tens, hundreds, or even thousands of square kilometers with no distinct plumes. A key question in implementing monitoring programs at the local, regional, and national level is, whether groundwater monitoring can be effectively used as a landowner compliance tool, as is currently done at point-source sites. We compare the efficiency of such traditional site-specific compliance networks in nonpoint source regulation with various designs of regional nonpoint source monitoring networks that could be used for compliance monitoring. We discuss advantages and disadvantages of the site vs. regional monitoring approaches with respect to effectively protecting groundwater resources impacted by nonpoint sources: Site-networks provide a tool to enforce compliance by an individual landowner. But the nonpoint source character of the contamination

  18. Updated study reporting levels (SRLs) for trace-element data collected for the California Groundwater Ambient Monitoring and Assessment (GAMA) Priority Basin Project, October 2009-March 2013

    Science.gov (United States)

    Davis, Tracy A.; Olsen, Lisa D.; Fram, Miranda S.; Belitz, Kenneth

    2014-01-01

    Groundwater samples have been collected in California as part of statewide investigations of groundwater quality conducted by the U.S. Geological Survey for the Groundwater Ambient Monitoring and Assessment (GAMA) Priority Basin Project (PBP). The GAMA-PBP is being conducted in cooperation with the California State Water Resources Control Board to assess and monitor the quality of groundwater resources used for drinking-water supply and to improve public knowledge of groundwater quality in California. Quality-control samples (source-solution blanks, equipment blanks, and field blanks) were collected in order to ensure the quality of the groundwater sample results. Olsen and others (2010) previously determined study reporting levels (SRLs) for trace-element results based primarily on field blanks collected in California from May 2004 through January 2008. SRLs are raised reporting levels used to reduce the likelihood of reporting false detections attributable to contamination bias. The purpose of this report is to identify any changes in the frequency and concentrations of detections in field blanks since the last evaluation and update the SRLs for more recent data accordingly. Constituents analyzed were aluminum (Al), antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), boron (B), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), lithium (Li), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se), silver (Ag), strontium (Sr), thallium (Tl), tungsten (W), uranium (U), vanadium (V), and zinc (Zn). Data from 179 field blanks and equipment blanks collected from March 2006 through March 2013 by the GAMA-PBP indicated that for trace elements that had a change in detection frequency and concentration since the previous review, the shift occurred near October 2009, in conjunction with a change in the capsule filters used by the study. Results for 89 field blanks and equipment blanks collected from October 2009 through March 2013 were

  19. Movement of a tritium plume in shallow groundwater at a legacy low-level radioactive waste disposal site in eastern Australia.

    Science.gov (United States)

    Hughes, C E; Cendón, D I; Harrison, J J; Hankin, S I; Johansen, M P; Payne, T E; Vine, M; Collins, R N; Hoffmann, E L; Loosz, T

    2011-10-01

    Between 1960 and 1968 low-level radioactive waste was buried in a series of shallow trenches near the Lucas Heights facility, south of Sydney, Australia. Groundwater monitoring carried out since the mid 1970s indicates that with the exception of tritium, no radioactivity above typical background levels has been detected outside the immediate vicinity of the trenches. The maximum tritium level detected in ground water was 390 kBq/L and the median value was 5400 Bq/L, decay corrected to the time of disposal. Since 1968, a plume of tritiated water has migrated from the disposal trenches and extends at least 100 m from the source area. Tritium in rainfall is negligible, however leachate from an adjacent and fill represents a significant additional tritium source. Study data indicate variation in concentration levels and plume distribution in response to wet and dry climatic periods and have been used to determine pathways for tritium migration through the subsurface.

  20. Correlation between geology and radon levels in groundwater, soil and indoor air in Bhilangana Valley, Garhwal Himalaya, India

    International Nuclear Information System (INIS)

    Choubey, V.M.; Ramola, R.C.

    1997-01-01

    Radon concentrations were measured in soil, air and groundwater in Bhilangana Valley, Garhwal Himalaya, India by using an LR-115 plastic track detector and radon emanometer. Radon concentrations were found to vary from 1 KBq/m 3 to 57 KBq/m 3 in soil, 5 Bq/l to 887 Bq/l in water and 95 Bq/m 3 to 208 Bq/m 3 in air. The recorded values are quite high due to associated uranium mineralization in the area. Radon concentration was also found to depend on the tectonic structure and geology of the area. (orig.)

  1. Uniqueness, intractability and exact algorithms: reflections on level-k phylogenetic networks

    NARCIS (Netherlands)

    L.J.J. van Iersel (Leo); S.M. Kelk (Steven); M. Mnich

    2009-01-01

    htmlabstractPhylogenetic networks provide a way to describe and visualize evolutionary histories that have undergone so-called reticulate evolutionary events such as recombination, hybridization or horizontal gene transfer. The level k of a network determines how non-treelike the evolution can be,

  2. Tracing groundwater with low-level detections of halogenated VOCs in a fractured carbonate-rock aquifer, Leetown Science Center, West Virginia, USA

    Science.gov (United States)

    Plummer, Niel; Sibrell, Philip L.; Casile, Gerolamo C.; Busenberg, Eurybiades; Hunt, Andrew G.; Schlosser, Peter

    2013-01-01

    Measurements of low-level concentrations of halogenated volatile organic compounds (VOCs) and estimates of groundwater age interpreted from 3H/3He and SF6 data have led to an improved understanding of groundwater flow, water sources, and transit times in a karstic, fractured, carbonate-rock aquifer at the Leetown Science Center (LSC), West Virginia. The sum of the concentrations of a set of 16 predominant halogenated VOCs (TDVOC) determined by gas chromatography with electron-capture detector (GC–ECD) exceeded that possible for air–water equilibrium in 34 of the 47 samples (median TDVOC of 24,800 pg kg−1), indicating that nearly all the water sampled in the vicinity of the LSC has been affected by addition of halogenated VOCs from non-atmospheric source(s). Leakage from a landfill that was closed and sealed nearly 20 a prior to sampling was recognized and traced to areas east of the LSC using low-level detection of tetrachloroethene (PCE), methyl chloride (MeCl), methyl chloroform (MC), dichlorodifluoromethane (CFC-12), and cis-1,2-dichloroethene (cis-1,2-DCE). Chloroform (CHLF) was the predominant VOC in water from domestic wells surrounding the LSC, and was elevated in groundwater in and near the Fish Health Laboratory at the LSC, where a leak of chlorinated water occurred prior to 2006. The low-level concentrations of halogenated VOCs did not exceed human or aquatic-life health criteria, and were useful in providing an awareness of the intrinsic susceptibility of the fractured karstic groundwater system at the LSC to non-atmospheric anthropogenic inputs. The 3H/3He groundwater ages of spring discharge from the carbonate rocks showed transient behavior, with ages averaging about 2 a in 2004 following a wet climatic period (2003–2004), and ages in the range of 4–7 a in periods of more average precipitation (2008–2009). The SF6 and CFC-12 data indicate older water (model ages of 10s of years or more) in the low-permeability shale of the Martinsburg

  3. Groundwater monitoring in the Savannah River Plant low-level waste burial ground: a summary and interpretation of the analytical data

    International Nuclear Information System (INIS)

    Ryan, J.P.

    1983-01-01

    This document describes chemical mechanisms that may affect trace-level radionuclide migration through acidic sandy clay soils in a humid environment, and summarizes the extensive chemical and radiochemical analyses of the groundwater directly below the SRP Low-Level Waste (LLW) Burial Ground (643-G). Anomalies were identified in the chemistry of individual wells which appear to be related to small amounts of fission product activity that have reached the water table. The chemical properties which were statistically related to trace-level transport of Cs-137 and Sr-90 were iron, potassium, sodium and calcium. Concentrations on the order of 100 ppM appear sufficient to affect nuclide migration. Several complexation mechanisms for plutonium migration were investigated, but most of these were shown to be incapable of mobilizing more than trace quantities of plutonium. The parameters of greatest importance were oxidation-reduction potential, pH, dissolved organic carbon, phosphate and carbonate. Of these, organic and phosphate complexation had the greatest potential for mobilizing plutonium in the SRP groundwater. In the absence of such complexants, plutonium would be essentially immobile in the soil/water system of the SRP burial ground. 50 references, 8 figures, 2 tables

  4. Statistical analysis of lake levels and field study of groundwater and surface-water exchanges in the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015: Chapter A of Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

    Science.gov (United States)

    Jones, Perry M.; Trost, Jared J.; Diekoff, Aliesha L.; Rosenberry, Donald O.; White, Eric A.; Erickson, Melinda L.; Morel, Daniel L.; Heck, Jessica M.

    2016-10-19

    Water levels declined from 2003 to 2011 in many lakes in Ramsey and Washington Counties in the northeast Twin Cities Metropolitan Area, Minnesota; however, water levels in other northeast Twin Cities Metropolitan Area lakes increased during the same period. Groundwater and surface-water exchanges can be important in determining lake levels where these exchanges are an important component of the water budget of a lake. An understanding of groundwater and surface-water exchanges in the northeast Twin Cities Metropolitan Area has been limited by the lack of hydrologic data. The U.S. Geological Survey, in cooperation with the Metropolitan Council and Minnesota Department of Health, completed a field and statistical study assessing lake-water levels and regional and local groundwater and surface-water exchanges near northeast Twin Cities Metropolitan Area lakes. This report documents the analysis of collected hydrologic, water-quality, and geophysical data; and existing hydrologic and geologic data to (1) assess the effect of physical setting and climate on lake-level fluctuations of selected lakes, (2) estimate potential percentages of surface-water contributions to well water across the northeast Twin Cities Metropolitan Area, (3) estimate general ages for waters extracted from the wells, and (4) assess groundwater inflow to lakes and lake-water outflow to aquifers downgradient from White Bear Lake. Statistical analyses of lake levels during short-term (2002–10) and long-term (1925–2014) periods were completed to help understand lake-level changes across the northeast Twin Cities Metropolitan Area. Comparison of 2002–10 lake levels to several landscape and geologic characteristics explained variability in lake-level changes for 96 northeast Twin Cities Metropolitan Area lakes. Application of several statistical methods determined that (1) closed-basin lakes (without an active outlet) had larger lake-level declines than flow-through lakes with an outlet; (2

  5. Natural radioactivity in groundwater sources in Ireland

    Energy Technology Data Exchange (ETDEWEB)

    Currivan, L.; Dowdall, A.; Mcginnity, P.; Ciara, M. [Radiological Protection Institute of Ireland (Ireland); Craig, M. [Environmental Protection Agency (Ireland)

    2014-07-01

    The Radiological Protection Institute of Ireland (RPII) in collaboration with the Irish Environmental Protection Agency (EPA) undertook a national survey of radioactivity in groundwater sources for compliance with parameters set out in the European Communities Drinking Water Directive. The Directive outlines the minimum requirements for the quality of drinking water and water intended for human consumption. Over two hundred samples were screened for radioactivity. Where indicated, analysis for individual radionuclide activity was undertaken and the radiation dose arising calculated. Furthermore, samples were analysed for radon concentration. This survey is the first comprehensive national survey of radioactivity in groundwater sources in Ireland. Approximately 18 per cent of drinking water in Ireland originates from groundwater and springs with the remainder from surface water. Between 2007 and 2011, water samples from a representative network of groundwater sources were analysed and assessed for compliance with the radioactivity parameters set out in the Drinking Water Directive. The assessment was carried out using the methodology for screening drinking water set out by the WHO. For practical purposes the WHO recommended screening levels for drinking water below which no further action is required of 100 mBq/l for gross alpha activity and 1000 mBq/l for gross beta activity were applied. Of the 203 groundwater sources screened for gross alpha and gross beta all met the gross beta activity criteria of less than 1000 mBq/l and 175 supplies had gross alpha activity concentrations of less than 100 mBq/l. For these sources no further analysis was required. The remaining 28 sources required further (radionuclide-specific) analysis from an alpha activity perspective. Results on ranges and distributions of radionuclide concentrations in groundwater as well as ingestion doses estimated for consumers of these water supplies will be presented. Document available in abstract

  6. Implementation of a network level protocol on a GIXINET type local network

    International Nuclear Information System (INIS)

    Loeuillet, J.L.

    1987-11-01

    The installation of a communication system for transferring results from several experiment laboratories to a computing center is described. The objectives of a useful bit rate of 24 kbs, low connection cost and simple infrastructure, extension of the network to 4 buildings situated within a radius of 300m, and connection in the most standardized fashion possible are attained by using the GIXINET local network and adopting the X25 packet protocol. Bit rates of 17.2 kbs for standard 128 octet packets, and 44 kbs for nonstandard packets (776 octets in this case) [fr

  7. Network Resilience Analysis: Review Of Concepts And A Country-Level. Case Study

    Directory of Open Access Journals (Sweden)

    Mariusz Kamola

    2014-01-01

    Full Text Available This paper presents the rationale behind performing an analysis of Internet resilience in the sense of maintaining a connection of autonomous systems in the presence of failures or attacks — on a level of a single country. Next, the graph of a network is constructed that represents interconnections between autonomous systems. The connectivity of the graph is examined for cases of link or node failure. Resilience metrics are proposed, focusing on a single autonomous system or on overall network reliability. The process of geographic location of networking infrastructure is presented, leading to an analysis of network resilience in the case of a joint failure of neighboring autonomous systems.

  8. A network-level explanation for the differences in HIV prevalence in ...

    African Journals Online (AJOL)

    A network-level explanation for the differences in HIV prevalence in South Africa's ... or ethnic groups may help explain the differential spread of HIV in South Africa. ... Keywords: concurrency, epidemiology, ethnicity, HIV/AIDS, race, social ...

  9. Development of a Regional Neural Network for Coastal Water Level Predictions

    National Research Council Canada - National Science Library

    Huang, Wenrui; Murray, Catherine; Kraus, Nicholas; Rosati, Julie

    2003-01-01

    .... Fortunately, the US National Oceanographic and Atmospheric Administration (NOAA) has a national network of water level monitoring stations distributed in regional scale that has been operating for several decades...

  10. How Should the Fires Network for the Future Force BDE Level UA be Structured?

    National Research Council Canada - National Science Library

    Ulloa, Juan

    2004-01-01

    ... to all available fires in the area of operations. This monograph constitutes an exploratory study of and preliminary analysis of the effects of networking all available fires at the brigade level UA...

  11. Social networks usage implications at the level of medical services consumption in Romania

    Directory of Open Access Journals (Sweden)

    Daniel Adrian Gardan

    2017-03-01

    The research results reveal key issues from the perspective of emotional involvement within consumption for the patients and the influence of key variables such as level of education, personality and lifestyle within social networks usage context.

  12. Conceptual plan for closer integration of network- and project-level pavement management

    Science.gov (United States)

    1998-01-01

    This report presents an evaluation of current performance modeling concepts and a feasibility study of the possibility of integrating network- and project-level performance prediction. The widely differing modeling methods in use today are reviewed a...

  13. An Experimental Exploration of the Impact of Network-Level Packet Loss on Network Intrusion Detection

    Science.gov (United States)

    2015-08-01

    fast recovery algorithms. Freemont (CA): Internet Engineering Task Force; 1997 Jan. RFC No.: 2001. 2. Smith SC, Hammell RJ, Parker TW, Marvel LM. A...2014. p. 1–6. 3. Sangster B, O’Connor T, Cook T, Fanelli R, Dean E , Adams WJ, Morrell C, Conti G. Toward instrumenting network warfare competitions

  14. Humanitarian Information Management Network Effectiveness: An Analysis at the Organizational and Network Levels

    Science.gov (United States)

    Ngamassi Tchouakeu, Louis-Marie

    2011-01-01

    Massive international response to humanitarian crises such as the South Asian Tsunami in 2004, the Hurricane Katrina in 2005 and the Haiti earthquake in 2010 highlights the importance of humanitarian inter-organizational collaboration networks, especially in information management and exchange. Despite more than a decade old call for more research…

  15. A High-Level Petri Net Framework for Genetic Regulatory Networks

    Directory of Open Access Journals (Sweden)

    Banks Richard

    2007-12-01

    Full Text Available To understand the function of genetic regulatory networks in the development of cellular systems, we must not only realise the individual network entities, but also the manner by which they interact. Multi-valued networks are a promising qualitative approach for modelling such genetic regulatory networks, however, at present they have limited formal analysis techniques and tools. We present a flexible formal framework for modelling and analysing multi-valued genetic regulatory networks using high-level Petri nets and logic minimization techniques. We demonstrate our approach with a detailed case study in which part of the genetic regulatory network responsible for the carbon starvation stress response in Escherichia coli is modelled and analysed. We then compare and contrast this multivalued model to a corresponding Boolean model and consider their formal relationship.

  16. Combining region- and network-level brain-behavior relationships in a structural equation model.

    Science.gov (United States)

    Bolt, Taylor; Prince, Emily B; Nomi, Jason S; Messinger, Daniel; Llabre, Maria M; Uddin, Lucina Q

    2018-01-15

    Brain-behavior associations in fMRI studies are typically restricted to a single level of analysis: either a circumscribed brain region-of-interest (ROI) or a larger network of brain regions. However, this common practice may not always account for the interdependencies among ROIs of the same network or potentially unique information at the ROI-level, respectively. To account for both sources of information, we combined measurement and structural components of structural equation modeling (SEM) approaches to empirically derive networks from ROI activity, and to assess the association of both individual ROIs and their respective whole-brain activation networks with task performance using three large task-fMRI datasets and two separate brain parcellation schemes. The results for working memory and relational tasks revealed that well-known ROI-performance associations are either non-significant or reversed when accounting for the ROI's common association with its corresponding network, and that the network as a whole is instead robustly associated with task performance. The results for the arithmetic task revealed that in certain cases, an ROI can be robustly associated with task performance, even when accounting for its associated network. The SEM framework described in this study provides researchers additional flexibility in testing brain-behavior relationships, as well as a principled way to combine ROI- and network-levels of analysis. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Analysis of stationary availability factor of two-level backbone computer networks with arbitrary topology

    Science.gov (United States)

    Rahman, P. A.

    2018-05-01

    This scientific paper deals with the two-level backbone computer networks with arbitrary topology. A specialized method, offered by the author for calculation of the stationary availability factor of the two-level backbone computer networks, based on the Markov reliability models for the set of the independent repairable elements with the given failure and repair rates and the methods of the discrete mathematics, is also discussed. A specialized algorithm, offered by the author for analysis of the network connectivity, taking into account different kinds of the network equipment failures, is also observed. Finally, this paper presents an example of calculation of the stationary availability factor for the backbone computer network with the given topology.

  18. Preliminary research on groundwater flow characteristics of the low- and Intermediate-level radioactive waste disposal site

    International Nuclear Information System (INIS)

    Koh, Young Kwon; Bae, Dae Seok; Kim, Geon Young; Ryu, Ji Hoon; Park, Kyung Woo; Ji, Sung Hoon; Kim, Kyung Su

    2009-08-01

    Preliminary site survey and candidate survey complements the purpose of the current site selection and disposal place selected for the study because of hydraulic to the geological survey done for the general idea was brought in the field of geochemistry survey was made. Therefore, this report hydraulic - the underlying structure of the model deterministic deformation zone model to focus on the configuration kept, according to data survey by hydraulic and hydraulic rock star pitcher trying to figure out the scope of the structure factors were hydraulic. Groundwater and related land place shares characteristics of the existing data and complementary research and laboratory research performed on the basis of geochemical data, based on the following major finding were present

  19. Using Conjugate Gradient Network to Classify Stress Level of Patients.

    Directory of Open Access Journals (Sweden)

    Er. S. Pawar

    2013-02-01

    Full Text Available Diagnosis of stress is important because it can cause many diseases e.g., heart disease, headache, migraine, sleep problems, irritability etc. Diagnosis of stress in patients often involves acquisition of biological signals for example heart rate, electrocardiogram (ECG, electromyography signals (EMG etc. Stress diagnosis using biomedical signals is difficult and since the biomedical signals are too complex to generate any rule an experienced person or expert is needed to determine stress levels. Also, it is not feasible to use all the features that are available or possible to extract from the signal. So, relevant features should be chosen from the extracted features that are capable to diagnose stress. Electronics devices are increasingly being seen in the field of medicine for diagnosis, therapy, checking of stress levels etc. The research and development work of medical electronics engineers leads to the manufacturing of sophisticated diagnostic medical equipment needed to ensure good health care. Biomedical engineering combines the design and problem solving skills of engineering with medical and biological sciences to improve health care diagnosis and treatment.

  20. Evaluation of the Impact of Groundwater Pumping on Freshwater-Saltwater Interface Fluctuations in a Coastal Aquifer of South Korea

    Science.gov (United States)

    Yoon, H.; Kim, Y.; Lee, S. H.; Ha, K.

    2017-12-01

    It is necessary to monitor the variation of freshwater-saltwater interface for the sustainable use of groundwater resources in coastal areas. In the present study, we developed a device to measure the location of the freshwater-saltwater interface based on the concept of the neutral buoyancy and installed it in a coastal aquifer of the western sea, South Korea. To evaluate the impact of pumping on the groundwater and saltwater-freshwater interface level, we designed nine different pumping scenarios and monitored the groundwater and saltwater-freshwater interface levels of pumping well and two observation wells. The result of monitoring groundwater level shows that the response of observation wells to the pumping is relatively fast and high, however, the response of freshwater-saltwater interface occurred when the pumping rate and duration are over 25m3/day and 48hours, respectively. For the prediction and simulation of the groundwater level fluctuation under groundwater pumping events, we designed a artificial neural network based time series model considering rainfall, tide, and pumping rate as input components. The result of the prediction shows that the correlation coefficient between observed and estimated groundwater levels is as high as 0.7. It is expected that the result of this research can provide useful information for the effective management of groundwater resources in the study area.

  1. Multi-level Control Framework for Enhanced Flexibility of Active Distribution Network

    DEFF Research Database (Denmark)

    Nainar, Karthikeyan; Pokhrel, Basanta Raj; Pillai, Jayakrishnan Radhakrishna

    2017-01-01

    In this paper, the control objectives of future active distribution networks with high penetration of renewables and flexible loads are analyzed and reviewed. From a state of the art review, the important control objectives seen from the perspective of a distribution system operator are identifie......-ordination and management of the network assets at different voltage levels and geographical locations. The paper finally shows the applicability of the multi-level control architecture to some of the key challenges in the distribution system operation by relevant scenarios....... to be hosting capacity improvement, high reliable operation and cost effective network management. Based on this review and a state of the art review concerning future distribution network control methods, a multi-level control architecture is constructed for an active distribution network, which satisfies...... the selected control objectives and provides enhanced flexibility. The control architecture is supported by generation/load forecasting and distribution state estimation techniques to improve the controllability of the network. The multi-level control architecture consists of three levels of hierarchical...

  2. Polarity-specific high-level information propagation in neural networks.

    Science.gov (United States)

    Lin, Yen-Nan; Chang, Po-Yen; Hsiao, Pao-Yueh; Lo, Chung-Chuan

    2014-01-01

    Analyzing the connectome of a nervous system provides valuable information about the functions of its subsystems. Although much has been learned about the architectures of neural networks in various organisms by applying analytical tools developed for general networks, two distinct and functionally important properties of neural networks are often overlooked. First, neural networks are endowed with polarity at the circuit level: Information enters a neural network at input neurons, propagates through interneurons, and leaves via output neurons. Second, many functions of nervous systems are implemented by signal propagation through high-level pathways involving multiple and often recurrent connections rather than by the shortest paths between nodes. In the present study, we analyzed two neural networks: the somatic nervous system of Caenorhabditis elegans (C. elegans) and the partial central complex network of Drosophila, in light of these properties. Specifically, we quantified high-level propagation in the vertical and horizontal directions: the former characterizes how signals propagate from specific input nodes to specific output nodes and the latter characterizes how a signal from a specific input node is shared by all output nodes. We found that the two neural networks are characterized by very efficient vertical and horizontal propagation. In comparison, classic small-world networks show a trade-off between vertical and horizontal propagation; increasing the rewiring probability improves the efficiency of horizontal propagation but worsens the efficiency of vertical propagation. Our result provides insights into how the complex functions of natural neural networks may arise from a design that allows them to efficiently transform and combine input signals.

  3. Parallel Fortran-MPI software for numerical inversion of the Laplace transform and its application to oscillatory water levels in groundwater environments

    Science.gov (United States)

    Zhan, X.

    2005-01-01

    A parallel Fortran-MPI (Message Passing Interface) software for numerical inversion of the Laplace transform based on a Fourier series method is developed to meet the need of solving intensive computational problems involving oscillatory water level's response to hydraulic tests in a groundwater environment. The software is a parallel version of ACM (The Association for Computing Machinery) Transactions on Mathematical Software (TOMS) Algorithm 796. Running 38 test examples indicated that implementation of MPI techniques with distributed memory architecture speedups the processing and improves the efficiency. Applications to oscillatory water levels in a well during aquifer tests are presented to illustrate how this package can be applied to solve complicated environmental problems involved in differential and integral equations. The package is free and is easy to use for people with little or no previous experience in using MPI but who wish to get off to a quick start in parallel computing. ?? 2004 Elsevier Ltd. All rights reserved.

  4. Raspberry Pi in-situ network monitoring system of groundwater flow and temperature integrated with OpenGeoSys

    Science.gov (United States)

    Park, Chan-Hee; Lee, Cholwoo

    2016-04-01

    Raspberry Pi series is a low cost, smaller than credit-card sized computers that various operating systems such as linux and recently even Windows 10 are ported to run on. Thanks to massive production and rapid technology development, the price of various sensors that can be attached to Raspberry Pi has been dropping at an increasing speed. Therefore, the device can be an economic choice as a small portable computer to monitor temporal hydrogeological data in fields. In this study, we present a Raspberry Pi system that measures a flow rate, and temperature of groundwater at sites, stores them into mysql database, and produces interactive figures and tables such as google charts online or bokeh offline for further monitoring and analysis. Since all the data are to be monitored on internet, any computers or mobile devices can be good monitoring tools at convenience. The measured data are further integrated with OpenGeoSys, one of the hydrogeological models that is also ported to the Raspberry Pi series. This leads onsite hydrogeological modeling fed by temporal sensor data to meet various needs.

  5. Study on application of adaptive fuzzy control and neural network in the automatic leveling system

    Science.gov (United States)

    Xu, Xiping; Zhao, Zizhao; Lan, Weiyong; Sha, Lei; Qian, Cheng

    2015-04-01

    This paper discusses the adaptive fuzzy control and neural network BP algorithm in large flat automatic leveling control system application. The purpose is to develop a measurement system with a flat quick leveling, Make the installation on the leveling system of measurement with tablet, to be able to achieve a level in precision measurement work quickly, improve the efficiency of the precision measurement. This paper focuses on the automatic leveling system analysis based on fuzzy controller, Use of the method of combining fuzzy controller and BP neural network, using BP algorithm improve the experience rules .Construct an adaptive fuzzy control system. Meanwhile the learning rate of the BP algorithm has also been run-rate adjusted to accelerate convergence. The simulation results show that the proposed control method can effectively improve the leveling precision of automatic leveling system and shorten the time of leveling.

  6. Evaluation of Groundwater Impacts to Support the National Environmental Policy Act Environmental Assessment for the INL Remote-Handled Low-Level Waste Disposal Project

    Energy Technology Data Exchange (ETDEWEB)

    Annette Schafer, Arthur S. Rood, A. Jeffrey Sondrup

    2011-12-23

    Groundwater impacts have been analyzed for the proposed remote-handled low-level waste disposal facility. The analysis was prepared to support the National Environmental Policy Act environmental assessment for the top two ranked sites for the proposed disposal facility. A four-phase screening and analysis approach was documented and applied. Phase I screening was site independent and applied a radionuclide half-life cut-off of 1 year. Phase II screening applied the National Council on Radiation Protection analysis approach and was site independent. Phase III screening used a simplified transport model and site-specific geologic and hydrologic parameters. Phase III neglected the infiltration-reducing engineered cover, the sorption influence of the vault system, dispersion in the vadose zone, vertical dispersion in the aquifer, and the release of radionuclides from specific waste forms. These conservatisms were relaxed in the Phase IV analysis which used a different model with more realistic parameters and assumptions. Phase I screening eliminated 143 of the 246 radionuclides in the inventory from further consideration because each had a half-life less than 1 year. An additional 13 were removed because there was no ingestion dose coefficient available. Of the 90 radionuclides carried forward from Phase I, 57 radionuclides had simulated Phase II screening doses exceeding 0.4 mrem/year. Phase III and IV screening compared the maximum predicted radionuclide concentration in the aquifer to maximum contaminant levels. Of the 57 radionuclides carried forward from Phase II, six radionuclides were identified in Phase III as having simulated future aquifer concentrations exceeding maximum contaminant limits. An additional seven radionuclides had simulated Phase III groundwater concentrations exceeding 1/100th of their respective maximum contaminant levels and were also retained for Phase IV analysis. The Phase IV analysis predicted that none of the thirteen remaining

  7. Conceptualization of the predevelopment groundwater flow system and transient water-level responses in Yucca Flat, Nevada National Security Site, Nevada

    Science.gov (United States)

    Fenelon, Joseph M.; Sweetkind, Donald S.; Elliott, Peggy E.; Laczniak, Randell J.

    2012-01-01

    Contaminants introduced into the subsurface of Yucca Flat, Nevada National Security Site, by underground nuclear testing are of concern to the U.S. Department of Energy and regulators responsible for protecting human health and safety. The potential for contaminant movement away from the underground test areas and into the accessible environment is greatest by groundwater transport. The primary hydrologic control on this transport is evaluated and examined through a set of contour maps developed to represent the hydraulic-head distribution within the two major aquifer systems underlying the area. Aquifers and confining units within these systems were identified and their extents delineated by merging and analyzing hydrostratigraphic framework models developed by other investigators from existing geologic information. Maps of the hydraulic-head distributions in the major aquifer systems were developed from a detailed evaluation and assessment of available water-level measurements. The maps, in conjunction with regional and detailed hydrogeologic cross sections, were used to conceptualize flow within and between aquifer systems. Aquifers and confining units are mapped and discussed in general terms as being one of two aquifer systems: alluvial-volcanic or carbonate. The carbonate aquifers are subdivided and mapped as independent regional and local aquifers, based on the continuity of their component rock. Groundwater flow directions, approximated from potentiometric contours, are indicated on the maps and sections and discussed for the alluvial-volcanic and regional carbonate aquifers. Flow in the alluvial-volcanic aquifer generally is constrained by the bounding volcanic confining unit, whereas flow in the regional carbonate aquifer is constrained by the siliceous confining unit. Hydraulic heads in the alluvial-volcanic aquifer typically range from 2,400 to 2,530 feet and commonly are elevated about 20-100 feet above heads in the underlying regional carbonate

  8. Groundwater level monitoring sampling and analysis plan for the environmental monitoring plan at waste area grouping 6, Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    This document is the Groundwater Level Monitoring Sampling and Analysis Plan (SAP) for Waste Area Grouping (WAG) 6 at Oak Ridge National Laboratory (ORNL). Note that this document is referred to as a SAP even though no sampling and analysis will be conducted. The term SAP is used for consistency. The procedures described herein are part of the Environmental Monitoring Plan (EMP) for WAG 6, which also includes monitoring tasks for seeps and springs, groundwater quality, surface water, and meteorological parameters. Separate SAPs are being issued concurrently to describe each of these monitoring programs. This SAP has been written for the use of the field personnel responsible for implementation of the EMP, with the intent that the field personnel will be able to take these documents to the field and quickly find the appropriate steps required to complete a specific task. In many cases, Field Operations Procedures (FOPs) will define the steps required for an activity. The FOPs for the EMP are referenced and briefly described in the relevant sections of the SAPs, and are contained within the FOP Manual. Both these documents (the SAP and the FOP Manual) will be available to personnel in the field.

  9. Well-construction, water-level, geophysical, and water-quality data for ground-water monitoring wells for Arnold Air Force Base, Tennessee

    Science.gov (United States)

    Hough, C.J.; Mahoney, E.N.; Robinson, J.A.

    1992-01-01

    Sixty-five wells were installed at 39 sites in the Arnold Air Force Base area in Coffee and Franklin Counties, Tennessee. The wells were installed to provide information on subsurface lithology, aquifer characteristics, ground-water levels, and ground-water quality. Well depths ranged from 11 to 384 feet. Water-quality samples were collected from 60 wells and analyzed for common inorganic ions, trace metals, and volatile organic compounds. The median dissolved-solids concentrations were 60 milligrams per liter in the shallow aquifer, 48 million gallons per liter in the Manchester aquifer, 1,235 milligrams per liter in the Fort Payne aquifer, and 1,712 milligrams per liter in the upper Central Basin aquifer. Caliper, temperature, natural gamma, electric, neutron porosity, gamma-gamma density, and acoustic velocity borehole-geophysical logs were obtained for the six deep wells completed below the Chattanooga Shale. Petrographic and modal analysis were performed on rock samples from each deep well. These six deep wells provide the first information in the study area on hydraulic head and water quality from below the Chattanooga Shale.

  10. Groundwater level monitoring sampling and analysis plan for the environmental monitoring plan at waste area grouping 6, Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1995-09-01

    This document is the Groundwater Level Monitoring Sampling and Analysis Plan (SAP) for Waste Area Grouping (WAG) 6 at Oak Ridge National Laboratory (ORNL). Note that this document is referred to as a SAP even though no sampling and analysis will be conducted. The term SAP is used for consistency. The procedures described herein are part of the Environmental Monitoring Plan (EMP) for WAG 6, which also includes monitoring tasks for seeps and springs, groundwater quality, surface water, and meteorological parameters. Separate SAPs are being issued concurrently to describe each of these monitoring programs. This SAP has been written for the use of the field personnel responsible for implementation of the EMP, with the intent that the field personnel will be able to take these documents to the field and quickly find the appropriate steps required to complete a specific task. In many cases, Field Operations Procedures (FOPs) will define the steps required for an activity. The FOPs for the EMP are referenced and briefly described in the relevant sections of the SAPs, and are contained within the FOP Manual. Both these documents (the SAP and the FOP Manual) will be available to personnel in the field

  11. Quantifying phosphorus levels in soils, plants, surface water, and shallow groundwater associated with bahiagrass-based pastures.

    Science.gov (United States)

    Sigua, Gilbert C; Hubbard, Robert K; Coleman, Samuel W

    2010-01-01

    Recent assessments of water quality status have identified eutrophication as one of the major causes of water quality 'impairment' not only in the USA but also around the world. In most cases, eutrophication has accelerated by increased inputs of phosphorus due to intensification of crop and animal production systems since the early 1990 s. Despite substantial measurements using both laboratory and field techniques, little is known about the spatial and temporal variability of phosphorus dynamics across landscapes, especially in agricultural landscapes with cow-calf operations. Critical to determining environmental balance and accountability is an understanding of phosphorus excreted by animals, phosphorus removal by plants, acceptable losses of phosphorus within the manure management and crop production systems into soil and waters, and export of phosphorus off-farm. Further research effort on optimizing forage-based cow-calf operations to improve pasture sustainability and protect water quality is therefore warranted. We hypothesized that properly managed cow-calf operations in subtropical agroecosystem would not be major contributors to excess loads of phosphorus in surface and ground water. To verify our hypothesis, we examined the comparative concentrations of total phosphorus among soils, forage, surface water, and groundwater beneath bahiagrass-based pastures with cow-calf operations in central Florida, USA. Soil samples were collected at 0-20; 20-40, 40-60, and 60-100 cm across the landscape (top slope, middle slope, and bottom slope) of 8 ha pasture in the fall and spring of 2004 to 2006. Forage availability and phosphorus uptake of bahiagrass were also measured from the top slope, middle slope, and bottom slope. Bi-weekly (2004-2006) groundwater and surface water samples were taken from wells located at top slope, middle slope, and bottom slope, and from the runoff/seepage area. Concentrations of phosphorus in soils, forage, surface water, and shallow

  12. Relations between total phosphorus and orthophosphorus concentrations and rainfall, surface-water discharge, and groundwater levels in Big Cypress Seminole Indian Reservation, Florida, 2014–16

    Science.gov (United States)

    McBride, W. Scott; Sifuentes, Dorothy F.

    2018-02-06

    nearby sites during the same period. Differences in concentrations can likely be explained by differences in sample collection methods, sampling locations, sample collection time, and the hydrology during sampling or by the number of samples collected. A major limitation of this study was the short duration of sample collection, which covers a limited range of hydrologic conditions within the BCSIR.The effect of surface-water and groundwater hydrologic conditions on TP and OP concentrations was assessed by using rainfall data and surface-water stage and discharge records. The highest TP and OP concentrations occurred during peak surface-water flows in the canals following long dry periods. Concentrations of TP and OP increased internal to the BCSIR in the western half of the BCSIR during wet periods, but increased concentrations tended to lag behind rainfall events, likely because control structures upstream of sampling sites do not release flows until the water levels in the canals reach predetermined levels. This pattern may indicate that bed sediments in the canals contain high concentrations of phosphorus that becomes resuspended during high flows or that phosphorus salts that had accumulated on dry land during dry periods are carried into the canals by runoff. The largest TP spikes usually occurred at the beginning of high-flow events, but then quickly tapered off even when flows remained high.Groundwater flows were assessed in the BCSIR by using groundwater level observations from two preexisting USGS monitoring well clusters, each characterized by a shallow well installed in the surficial aquifer system and a deeper well installed in the intermediate aquifer system. Groundwater levels were evaluated with respect to surface-water levels and discharge in the BCSIR during the period of surface-water sampling. During dry conditions water levels in canals were often higher than groundwater levels in the surficial aquifer, indicating the potential for surface water to

  13. Groundwater Potential

    African Journals Online (AJOL)

    big timmy

    4Department of Geology, Ekiti State University, Ado-Ekiti, Nigeria. Corresponding ... integrated for the classification of the study area into different groundwater potential zones. .... table is mainly controlled by subsurface movement of water into ...

  14. Energy Efficient Four Level Cooperative Opportunistic Communication for Wireless Personal Area Networks (WPAN)

    DEFF Research Database (Denmark)

    Rohokale, Vandana M.; Inamdar, Sandeep; Prasad, Neeli R.

    2013-01-01

    For wireless sensor networks (WSN),energy is a scarce resource. Due to limited battery resources, the energy consumption is the critical issue for the transmission as well as reception of the signals in the wireless communication. WSNs are infrastructure-less shared network demanding more energy...... consumption due to collaborative transmissions. This paper proposes a new cooperative opportunistic four level model for IEEE 802.15.4 Wireless Personal Area Network (WPAN).The average per node energy consumption is observed merely about 0.17mJ for the cooperative wireless communication which proves...... the proposed mechanism to be energy efficient. This paper further proposes four levels of cooperative data transmission from source to destination to improve network coverage with energy efficiency....

  15. A BHR Composite Network-Based Visualization Method for Deformation Risk Level of Underground Space.

    Directory of Open Access Journals (Sweden)

    Wei Zheng

    Full Text Available This study proposes a visualization processing method for the deformation risk level of underground space. The proposed method is based on a BP-Hopfield-RGB (BHR composite network. Complex environmental factors are integrated in the BP neural network. Dynamic monitoring data are then automatically classified in the Hopfield network. The deformation risk level is combined with the RGB color space model and is displayed visually in real time, after which experiments are conducted with the use of an ultrasonic omnidirectional sensor device for structural deformation monitoring. The proposed method is also compared with some typical methods using a benchmark dataset. Results show that the BHR composite network visualizes the deformation monitoring process in real time and can dynamically indicate dangerous zones.

  16. Integrating Micro-level Interactions with Social Network Analysis in Tie Strength Research

    DEFF Research Database (Denmark)

    Torre, Osku; Gupta, Jayesh Prakash; Kärkkäinen, Hannu

    2017-01-01

    of tie strength based on reciprocal interaction from publicly available Facebook data, and suggest that this approach could work as a basis for further tie strength studies. Our approach makes use of weak tie theory, and enables researchers to study micro-level interactions (i.e. discussions, messages......A social tie is a target for ongoing, high-level scientific debate. Measuring the tie strength in social networks has been an important topic for academic studies since Mark Granovetter's seminal papers in 1970's. However, it is still a problematic issue mainly for two reasons: 1) existing tie...... strengthening process in online social networks. Therefore, we suggest a new approach to tie strength research, which focuses on studying communication patterns (edges) more rather than actors (nodes) in a social network. In this paper we build a social network analysis-based approach to enable the evaluation...

  17. Assessment of groundwater response to droughts in a complex runoff-dominated watershed by using an integrated hydrologic model

    Science.gov (United States)

    Woolfenden, L. R.; Hevesi, J. A.; Nishikawa, T.

    2014-12-01

    Groundwater is an important component of the water supply, especially during droughts, within the Santa Rosa Plain watershed (SRPW), California, USA. The SRPW is 680 km2 and includes a network of natural and engineered stream channels. Streamflow is strongly seasonal, with high winter flows, predominantly intermittent summer flows, and comparatively rapid response time to larger storms. Groundwater flow is influenced primarily by complex geology, spatial and temporal variation in recharge, and pumping for urban, agricultural, and rural demands. Results from an integrated hydrologic model (GSFLOW) for the SRPW were analyzed to assess the effect of droughts on groundwater resources during water years 1976-2010. Model results indicate that, in general, below-average precipitation during historical drought periods reduced groundwater recharge (focused within stream channels and diffuse outside of channels on alluvial plains), groundwater evapotranspiration (ET), and groundwater discharge to streams (baseflow). In addition, recharge during wet periods was not sufficient to replenish groundwater-storage losses caused by drought and groundwater pumping, resulting in an overall 150 gigaliter loss in groundwater storage for water years 1976-2010. During drought periods, lower groundwater levels from reduced recharge broadly increased the number and length of losing-stream reaches, and seepage losses in streams became a higher percentage of recharge relative to the diffuse recharge outside of stream channels (for example, seepage losses in streams were 36% of recharge in 2006 and 57% at the end of the 2007-09 drought). Reductions in groundwater storage during drought periods resulted in decreased groundwater ET (loss of riparian habitat) and baseflow, especially during the warmer and dryer months (May through September) when groundwater is the dominant component of streamflow.

  18. Teacher Candidates' Opinions Regarding Instructional and Safe Use of Social Networks and Internet Addiction Risk Levels

    Directory of Open Access Journals (Sweden)

    Enis Fasli

    2018-05-01

    Full Text Available In conjunction with the development and advancement of internet technologies, social networking sites have created a socialization environment. Instructors point out that these tools must be used as an active and different form of communication with students. Also, participation of the students through social networking sites should be encouraged. However, the risk of internet addiction has also become widespread on the increase use of social networks. The aim of this research is to “determine the opinions of teacher candidates on the use of social networking sites in education and Internet addiction risk levels”. General survey model was used in this research in order to determine the opinions regarding social networks of teacher candidates from the education faculties in the Turkish Republic of Northern Cyprus and figure out their internet addiction risk levels. “Use of Social Networks in Education Scale” developed by Ozturk and Akgun and “Internet Addiction Test” developed by Young were used in this research. According to the results of the study, it has been figured out that almost all of the teacher candidates think that sharing information through social networking sites is either partially safe or not safe. Besides, most of the teacher candidates feel anxious about keeping information as confidential. Another important result is that teacher candidates are internet users at an average level. It also shows that they might spend too much time on the internet however they use internet in a controlled manner.

  19. Three-Level Z-Source Inverters Using a Single LC Impedance Network

    DEFF Research Database (Denmark)

    Loh, Poh Chiang; Lim, Sok Wei; Gao, Feng

    2007-01-01

    two LC impedance networks and two isolated dc sources, which can significantly increase the overall system cost and require a more complex modulator for balancing the network inductive voltage boosting. Offering a number of less costly alternatives, this letter presents the design and control of two...... three-level Z-source inverters, whose output voltage can be stepped down or up using only a single LC impedance network connected between the dc input source and either a neutral-point-clamped (NPC) or dc-link cascaded inverter circuitry. Through careful design of their modulation scheme, both inverters...

  20. Risk Evaluation of Railway Coal Transportation Network Based on Multi Level Grey Evaluation Model

    Science.gov (United States)

    Niu, Wei; Wang, Xifu

    2018-01-01

    The railway transport mode is currently the most important way of coal transportation, and now China’s railway coal transportation network has become increasingly perfect, but there is still insufficient capacity, some lines close to saturation and other issues. In this paper, the theory and method of risk assessment, analytic hierarchy process and multi-level gray evaluation model are applied to the risk evaluation of coal railway transportation network in China. Based on the example analysis of Shanxi railway coal transportation network, to improve the internal structure and the competitiveness of the market.

  1. Identification of Pavement Distress Types and Pavement Condition Evaluation Based on Network Level Inspection for Jazan City Road Network

    Directory of Open Access Journals (Sweden)

    M Mubaraki

    2014-06-01

    Full Text Available The first step in establishing a pavement management system (PMS is road network identification. An important feature of a PMS is the ability to determine the current condition of a road network and predict its future condition. Pavement condition evaluation may involve structure, roughness, surface distress, and safety evaluation. In this study, a pavement distress condition rating procedure was used to achieve the objectives of this study. The main objectives of this study were to identify the common types of distress that exist on the Jazan road network (JRN, either on main roads or secondary roads, and to evaluate the pavement condition based on network level inspection. The study was conducted by collecting pavement distress types from 227 sample units on main roads and 500 sample units from secondary roads. Data were examined through analysis of common types of distress identified in both main and secondary roads. Through these data, pavement condition index (PCI for each sample unit was then calculated. Through these calculations, average PCIs for the main and secondary roads were determined. Results indicated that the most common pavement distress types on main roads were patching and utility cut patching, longitudinal and transverse cracking, polished aggregate, weathering and raveling, and alligator cracking. The most common pavement distress types on secondary roads were weathering and raveling, patching and utility cut patching, longitudinal and transverse cracking, potholes, and alligator cracking. The results also indicated that 65% of Jazan's main road network has an average pavement condition rating of very good while only 30% of Jazan's secondary roads network has an average pavement condition.

  2. Analysis on the University’s Network Security Level System in the Big Data Era

    Science.gov (United States)

    Li, Tianli

    2017-12-01

    The rapid development of science and technology, the continuous expansion of the scope of computer network applications, has gradually improved the social productive forces, has had a positive impact on the increase production efficiency and industrial scale of China's different industries. Combined with the actual application of computer network in the era of large data, we can see the existence of influencing factors such as network virus, hacker and other attack modes, threatening network security and posing a potential threat to the safe use of computer network in colleges and universities. In view of this unfavorable development situation, universities need to pay attention to the analysis of the situation of large data age, combined with the requirements of network security use, to build a reliable network space security system from the equipment, systems, data and other different levels. To avoid the security risks exist in the network. Based on this, this paper will analyze the hierarchical security system of cyberspace security in the era of large data.

  3. Geochemical study of change of groundwater quality by substances in strata with high level radioactive waste geological disposal

    International Nuclear Information System (INIS)

    Kanazawa, Yasuo; Tsukimura, Katsuhiro; Seki, Yoji; Hamazaki, Satoshi; Nakajima, Terumasa; Aoki, Masahiro; Kanai, Yutaka; Kamioka, Hikari

    1998-01-01

    Weathered rock and soil contain large amount of fine amorphous which make large effect on water quality. By X-ray diffraction method, we found Kanto loam formation contained 90% amorphous. Quartz, gibbsite and feldspar were observed as crystals. Change of groundwater quality during infiltration was studied by the field experiments. Samples were collected at drainage basin in small valleys, lower a few ten to hundred meters from the top. Surface substances and water samples were collected in runoff and spring water in the area of Kaba granites, Abukuma granites, Abukuma metamorphic rocks and sedimentary rocks. Water temperature, redox potential, electric conductivity, dissolved oxygen concentration, pH and alkalinity were measured in the field. Samples were analyzed by ion chromatography and atomic absorption spectrophotometer. These samples have been investigating. The results obtained showed that water in chart did not react with rock, and the water quality in granite area was different from that of metamorphic rocks, sandstone, chart and green tuff area. (S.Y.)

  4. Sea Levels Online: Sea Level Variations of the United States Derived from National Water Level Observation Network Stations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water level records are a combination of the fluctuations of the ocean and the vertical land motion at the location of the station. Monthly mean sea level (MSL)...

  5. Groundwater data collection for the Quinault Indian Nation, Grays Harbor and Jefferson Counties, Washington

    Science.gov (United States)

    Kahle, Sue C.; Fasser, Elisabeth T.; Olsen, Theresa D.

    2017-11-03

    Groundwater data were collected on the Quinault Indian Reservation to provide the Quinualt Indian Nation (QIN) with basic knowledge of the existing wells and springs on the reservation, and to establish a water-level network to be monitored by QIN to begin building a long-term groundwater dataset. The 327 mi2 Quinault Indian Reservation is located within the heavily forested Queets-Quinault watershed along the west-central coast of Washington and includes the coastal communities of Taholah and Queets, and the inland community of Amanda Park. Groundwater data were collected or compiled for 87 sites—82 wells and 5 springs. In October 2016, a field inventory was done to locate the sites and acquire site data. Groundwater levels were measured in 15 of the field-inventoried wells and 3 of those wells were observed as flowing (artesian). A monthly groundwater‑level monitoring network of 13 wells was established by the U.S. Geological Survey in March 2017, and the network was transferred to QIN in June 2017 for continued measurements.Several data needs were identified that would provide a more complete understanding of the groundwater system of the Quinault Indian Reservation. The collection of monthly water-level data for multiple years is an important first step in understanding seasonal and long term changes in water levels. Additionally, the collection of baseline groundwater chemistry and quality data across the reservation would help with future efforts to monitor existing and potentially changing groundwater quality conditions. Development of a water budget of the Queets-Quinault Watershed and the reservation within that area would provide water users with a better understanding of this important resource and provide needed information about the competing demands on local water sources.

  6. 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...

  7. Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Volume 1. Guideline approach

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, C.S.; Cole, C.R.

    1985-05-01

    This document was written for the National Low-Level Waste Management Program to provide guidance for managers and site operators who need to select ground-water transport codes for assessing shallow-land burial site performance. The guidance given in this report also serves the needs of applications-oriented users who work under the direction of a manager or site operator. The guidelines are published in two volumes designed to support the needs of users having different technical backgrounds. An executive summary, published separately, gives managers and site operators an overview of the main guideline report. This volume includes specific recommendations for decision-making managers and site operators on how to use these guidelines. The more detailed discussions about the code selection approach are provided. 242 refs., 6 figs.

  8. Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Volume 1. Guideline approach

    International Nuclear Information System (INIS)

    Simmons, C.S.; Cole, C.R.

    1985-05-01

    This document was written for the National Low-Level Waste Management Program to provide guidance for managers and site operators who need to select ground-water transport codes for assessing shallow-land burial site performance. The guidance given in this report also serves the needs of applications-oriented users who work under the direction of a manager or site operator. The guidelines are published in two volumes designed to support the needs of users having different technical backgrounds. An executive summary, published separately, gives managers and site operators an overview of the main guideline report. This volume includes specific recommendations for decision-making managers and site operators on how to use these guidelines. The more detailed discussions about the code selection approach are provided. 242 refs., 6 figs

  9. Randomization and resilience of brain functional networks as systems-level endophenotypes of schizophrenia.

    Science.gov (United States)

    Lo, Chun-Yi Zac; Su, Tsung-Wei; Huang, Chu-Chung; Hung, Chia-Chun; Chen, Wei-Ling; Lan, Tsuo-Hung; Lin, Ching-Po; Bullmore, Edward T

    2015-07-21

    Schizophrenia is increasingly conceived as a disorder of brain network organization or dysconnectivity syndrome. Functional MRI (fMRI) networks in schizophrenia have been characterized by abnormally random topology. We tested the hypothesis that network randomization is an endophenotype of schizophrenia and therefore evident also in nonpsychotic relatives of patients. Head movement-corrected, resting-state fMRI data were acquired from 25 patients with schizophrenia, 25 first-degree relatives of patients, and 29 healthy volunteers. Graphs were used to model functional connectivity as a set of edges between regional nodes. We estimated the topological efficiency, clustering, degree distribution, resilience, and connection distance (in millimeters) of each functional network. The schizophrenic group demonstrated significant randomization of global network metrics (reduced clustering, greater efficiency), a shift in the degree distribution to a more homogeneous form (fewer hubs), a shift in the distance distribution (proportionally more long-distance edges), and greater resilience to targeted attack on network hubs. The networks of the relatives also demonstrated abnormal randomization and resilience compared with healthy volunteers, but they were typically less topologically abnormal than the patients' networks and did not have abnormal connection distances. We conclude that schizophrenia is associated with replicable and convergent evidence for functional network randomization, and a similar topological profile was evident also in nonpsychotic relatives, suggesting that this is a systems-level endophenotype or marker of familial risk. We speculate that the greater resilience of brain networks may confer some fitness advantages on nonpsychotic relatives that could explain persistence of this endophenotype in the population.

  10. Damage Level Prediction of Reinforced Concrete Building Based on Earthquake Time History Using Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Suryanita Reni

    2017-01-01

    Full Text Available The strong motion earthquake could cause the building damage in case of the building not considered in the earthquake design of the building. The study aims to predict the damage-level of building due to earthquake using Artificial Neural Networks method. The building model is a reinforced concrete building with ten floors and height between floors is 3.6 m. The model building received a load of the earthquake based on nine earthquake time history records. Each time history scaled to 0,5g, 0,75g, and 1,0g. The Artificial Neural Networks are designed in 4 architectural models using the MATLAB program. Model 1 used the displacement, velocity, and acceleration as input and Model 2 used the displacement only as the input. Model 3 used the velocity as input, and Model 4 used the acceleration just as input. The output of the Neural Networks is the damage level of the building with the category of Safe (1, Immediate Occupancy (2, Life Safety (3 or in a condition of Collapse Prevention (4. According to the results, Neural Network models have the prediction rate of the damage level between 85%-95%. Therefore, one of the solutions for analyzing the structural responses and the damage level promptly and efficiently when the earthquake occurred is by using Artificial Neural Network

  11. Altered Brain Network in Amyotrophic Lateral Sclerosis: A Resting Graph Theory-Based Network Study at Voxel-Wise Level.

    Science.gov (United States)

    Zhou, Chaoyang; Hu, Xiaofei; Hu, Jun; Liang, Minglong; Yin, Xuntao; Chen, Lin; Zhang, Jiuquan; Wang, Jian

    2016-01-01

    Amyotrophic lateral sclerosis (ALS) is a rare degenerative disorder characterized by loss of upper and lower motor neurons. Neuroimaging has provided noticeable evidence that ALS is a complex disease, and shown that anatomical and functional lesions extend beyond precentral cortices and corticospinal tracts, to include the corpus callosum; frontal, sensory, and premotor cortices; thalamus; and midbrain. The aim of this study is to investigate graph theory-based functional network abnormalities at voxel-wise level in ALS patients on a whole brain scale. Forty-three ALS patients and 44 age- and sex-matched healthy volunteers were enrolled. The voxel-wise network degree centrality (DC), a commonly employed graph-based measure of network organization, was used to characterize the alteration of whole brain functional network. Compared with the controls, the ALS patients showed significant increase of DC in the left cerebellum posterior lobes, bilateral cerebellum crus, bilateral occipital poles, right orbital frontal lobe, and bilateral prefrontal lobes; significant decrease of DC in the bilateral primary motor cortex, bilateral sensory motor region, right prefrontal lobe, left bilateral precuneus, bilateral lateral temporal lobes, left cingulate cortex, and bilateral visual processing cortex. The DC's z-scores of right inferior occipital gyrus were significant negative correlated with the ALSFRS-r scores. Our findings confirm that the regions with abnormal network DC in ALS patients were located in multiple brain regions including primary motor, somatosensory and extra-motor areas, supporting the concept that ALS is a multisystem disorder. Specifically, our study found that DC in the visual areas was altered and ALS patients with higher DC in right inferior occipital gyrus have more severity of disease. The result demonstrated that the altered DC value in this region can probably be used to assess severity of ALS.

  12. Altered brain network in Amyotrophic Lateral Sclerosis: a resting graph theory-based network study at voxel-wise level

    Directory of Open Access Journals (Sweden)

    Chaoyang eZhou

    2016-05-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is a rare degenerative disorder characterized by loss of upper and lower motor neurons. Neuroimaging has provided noticeable evidence that ALS is a complex disease, and shown that anatomical and functional lesions extend beyond precentral cortices and corticospinal tracts, to include the corpus callosum; frontal, sensory, and premotor cortices; thalamus; and midbrain. The aim of this study is to investigate graph theory-based functional network abnormalities at voxel-wise level in ALS patients on a whole brain scale. Forty-three ALS patients and 44 age- and sex- matched healthy volunteers were enrolled. The voxel-wise network degree centrality (DC, a commonly employed graph-based measure of network organization, was used to characterize the alteration of whole brain functional network. Compared with the controls, the ALS patients showed significant increase of DC in the left cerebellum posterior lobes, bilateral cerebellum crus, bilateral occipital poles, right orbital frontal lobe and bilateral prefrontal lobes; significant decrease of DC in the bilateral primary motor cortex, bilateral sensory motor region, right prefrontal lobe, left bilateral precuneus, bilateral lateral temporal lobes, left cingulate cortex, and bilateral visual processing cortex. The DC’s z-scores of right inferior occipital gyrus were significant negative correlated with the ALSFRS-r scores. Our findings confirm that the regions with abnormal network DC in ALS patients were located in multiple brain regions including primary motor, somatosensory and extra-motor areas, supporting the concept that ALS is a multisystem disorder. Specifically, our study found that DC in the visual areas was altered and ALS patients with higher DC in right inferior occipital gyrus have more severity of disease. The result demonstrated that the altered DC value in this region can probably be used to assess severity of ALS.

  13. Evaluating C-RAN Fronthaul Functional Splits in Terms of Network Level Energy and Cost Savings

    DEFF Research Database (Denmark)

    Checko, Aleksandra; Popovska Avramova, Andrijana; Berger, Michael Stübert

    2016-01-01

    The placement of the complete baseband processing in a centralized pool results in high data rate requirement and inflexibility of the fronthaul network, which challenges the energy and cost effectiveness of the cloud radio access network (C-RAN). Recently, redesign of the C-RAN through functional...... split in the baseband processing chain has been proposed to overcome these challenges. This paper evaluates, by mathematical and simulation methods, different splits with respect to network level energy and cost efficiency having in the mind the expected quality of service.The proposed mathematical...... model quantifies the multiplexing gains and the trade-offs between centralization and decentralization concerning the cost of the pool, fronthaul network capacity and resource utilization. The event-based simulation captures the influence of the traffic load dynamics and traffic type variation...

  14. The effect of increasing levels of embedded generation on the distribution network. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Collinson, A; Earp, G K; Howson, D; Owen, R D; Wright, A J

    1999-10-01

    This report was commissioned as part of the EA Technology Strategic Technology Programme under guidance of the Module 5 (Embedded Generation) Steering Group. This report aims to provide information related to the distribution and supply of electricity in the context of increasing levels of embedded generation. There is a brief description of the operating environment within which electricity companies in the UK must operate. Technical issues related to the connection of generation to the existing distribution infrastructure are highlighted and the design philosophy adopted by network designers in accommodating applications for the connection of embedded generation to the network is discussed. The effects embedded generation has on the network and the issues raised are presented as many of them present barriers to the connection of embedded generators. The final chapters cover the forecast of required connection to 2010 and solutions to restrictions preventing the connection of more embedded generation to the network. (author)

  15. DReAM: Demand Response Architecture for Multi-level District Heating and Cooling Networks

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Saptarshi; Chandan, Vikas; Arya, Vijay; Kar, Koushik

    2017-05-19

    In this paper, we exploit the inherent hierarchy of heat exchangers in District Heating and Cooling (DHC) networks and propose DReAM, a novel Demand Response (DR) architecture for Multi-level DHC networks. DReAM serves to economize system operation while still respecting comfort requirements of individual consumers. Contrary to many present day DR schemes that work on a consumer level granularity, DReAM works at a level of hierarchy above buildings, i.e. substations that supply heat to a group of buildings. This improves the overall DR scalability and reduce the computational complexity. In the first step of the proposed approach, mathematical models of individual substations and their downstream networks are abstracted into appropriately constructed low-complexity structural forms. In the second step, this abstracted information is employed by the utility to perform DR optimization that determines the optimal heat inflow to individual substations rather than buildings, in order to achieve the targeted objectives across the network. We validate the proposed DReAM framework through experimental results under different scenarios on a test network.

  16. An Integrative Bioinformatics Framework for Genome-scale Multiple Level Network Reconstruction of Rice

    Directory of Open Access Journals (Sweden)

    Liu Lili

    2013-06-01

    Full Text Available Understanding how metabolic reactions translate the genome of an organism into its phenotype is a grand challenge in biology. Genome-wide association studies (GWAS statistically connect genotypes to phenotypes, without any recourse to known molecular interactions, whereas a molecular mechanistic description ties gene function to phenotype through gene regulatory networks (GRNs, protein-protein interactions (PPIs and molecular pathways. Integration of different regulatory information levels of an organism is expected to provide a good way for mapping genotypes to phenotypes. However, the lack of curated metabolic model of rice is blocking the exploration of genome-scale multi-level network reconstruction. Here, we have merged GRNs, PPIs and genome-scale metabolic networks (GSMNs approaches into a single framework for rice via omics’ regulatory information reconstruction and integration. Firstly, we reconstructed a genome-scale metabolic model, containing 4,462 function genes, 2,986 metabolites involved in 3,316 reactions, and compartmentalized into ten subcellular locations. Furthermore, 90,358 pairs of protein-protein interactions, 662,936 pairs of gene regulations and 1,763 microRNA-target interactions were integrated into the metabolic model. Eventually, a database was developped for systematically storing and retrieving the genome-scale multi-level network of rice. This provides a reference for understanding genotype-phenotype relationship of rice, and for analysis of its molecular regulatory network.

  17. Neural Network with Local Memory for Nuclear Reactor Power Level Control

    International Nuclear Information System (INIS)

    Uluyol, Oender; Ragheb, Magdi; Tsoukalas, Lefteri

    2001-01-01

    A methodology is introduced for a neural network with local memory called a multilayered local output gamma feedback (LOGF) neural network within the paradigm of locally-recurrent globally-feedforward neural networks. It appears to be well-suited for the identification, prediction, and control tasks in highly dynamic systems; it allows for the presentation of different timescales through incorporation of a gamma memory. A learning algorithm based on the backpropagation-through-time approach is derived. The spatial and temporal weights of the network are iteratively optimized for a given problem using the derived learning algorithm. As a demonstration of the methodology, it is applied to the task of power level control of a nuclear reactor at different fuel cycle conditions. The results demonstrate that the LOGF neural network controller outperforms the classical as well as the state feedback-assisted classical controllers for reactor power level control by showing a better tracking of the demand power, improving the fuel and exit temperature responses, and by performing robustly in different fuel cycle and power level conditions

  18. Control of Groundwater Pollution from Animal Feeding Operations: A Farm-Level Dynamic Model for Policy Analysis

    Science.gov (United States)

    Wang, J.; Baerenklau, K.

    2012-12-01

    Consolidation in livestock production generates higher farm incomes due to economies of scale, but it also brings waste disposal problems. Over-application of animal waste on adjacent land produces adverse environmental and health effects, including groundwater nitrate pollution. The situation is particularly noticeable in California. In respond to this increasingly severe problem, EPA published a type of command-and-control regulation for concentrated animal feeding operations (CAFOs) in 2003. The key component of the regulation is its nutrient management plans (NMPs), which intend to limit the land application rates of animal waste. Although previous studies provide a full perspective on potential economic impacts for CAFOs to meet nutrient standards, their models are static and fail to reflect changes in management practices other than spreading manure on additional land and changing cropping patterns. We develop a dynamic environmental-economic modeling framework for representative CAFOs. The framework incorporates four models (i.e., animal model, crop model, hydrologic model, and economic model) that include various components such as herd management, manure handling system, crop rotation, water sources, irrigation system, waste disposal options, and pollutant emissions. We also include the dynamics of soil characteristics in the rootzone as well as the spatial heterogeneity of the irrigation system. The operator maximizes discounted total farm profit over multiple periods subject to environmental regulations. Decision rules from the dynamic optimization problem demonstrate best management practices for CAFOs to improve their economic and environmental performance. Results from policy simulations suggest that direct quantity restrictions of emission or incentive-based emission policies are much more cost-effective than the standard approach of limiting the amount of animal waste that may be applied to fields (as shown in the figure below); reason being

  19. Belgrade waterworks groundwater source

    International Nuclear Information System (INIS)

    Sotic, A.; Dasic, M.; Vukcevic, G.; Vasiljevic, Lj.; Nikolic, S.

    2002-01-01

    Paper deals with Belgrade Waterworks groundwater source, its characte