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1. Hydrogeological conceptual model building and testing: A review

Author:
Enemark, Trine; Peeters, Luk J.M.; Mallants, Dirk; Batelaan, Okke
Source:
Journal of hydrology 2019 v.569 pp. 310-329
ISSN:
0022-1694
Subject:
groundwater; groundwater flow,   etc   ; guidelines; models; prediction; uncertainty;     Show all 6 Subjects
Abstract:
... Hydrogeological conceptual models are collections of hypotheses describing the understanding of groundwater systems and they are considered one of the major sources of uncertainty in groundwater flow and transport modelling. A common method for characterizing the conceptual uncertainty is the multi-model approach, where alternative plausible conceptual models are developed and evaluated. This revi ...
DOI:
10.1016/j.jhydrol.2018.12.007

2. Accurate approximate semi-analytical solutions to the Boussinesq groundwater flow equation for recharging and discharging of horizontal unconfined aquifers

Author:
Hayek, Mohamed
Source:
Journal of hydrology 2019 v.570 pp. 411-422
ISSN:
0022-1694
Subject:
groundwater; groundwater flow,   etc   ; dewatering; equations; streams; unconfined aquifer; water table;     Show all 7 Subjects
Abstract:
... The Boussinesq equation is usually used to describe one-dimensional unconfined groundwater movement. Solutions of this equation are important as they provide useful insights regarding the water table response to stream level variations and allow us to quantify the exchange flow between the stream and the aquifer. Due to the nonlinearity of the Boussinesq equation, the solutions are generally obtai ...
DOI:
10.1016/j.jhydrol.2018.12.057

3. An assessment of the replicability of a standard and modified sanitary risk protocol for groundwater sources in Greater Accra

Author:
Yentumi, W.; Dzodzomenyo, M.; Sashie-Doe, K.; Wright, J.
Source:
Environmental monitoring and assessment 2019 v.191 no.2 pp. 59
ISSN:
0167-6369
Subject:
groundwater; groundwater contamination,   etc   ; pipes; protocols; risk; sewage; surveys; wells; Ghana;     Show all 9 Subjects
Abstract:
... Sanitary risk inspection, the systematic observation of contamination hazards, is often used to manage safety of water sources such as wells and boreholes. However, the replicability of sanitary risk inspections undertaken by different observers has not been studied. This study aimed to assess the replicability of sanitary risk inspections by two different observers in urban and peri-urban neighbo ...
DOI:
10.1007/s10661-018-7174-5

4. A semi-analytical solution for groundwater flow-field delineation near pumping/injection wells in confined aquifers

Author:
Bica, Ioan; Boukhemacha, Mohamed Amine; Groza, Ghiocel
Source:
Hydrogeology journal 2019 v.27 no.1 pp. 61-71
ISSN:
1431-2174
Subject:
groundwater; groundwater flow,   etc   ; confined aquifer; isotropy; mathematical models; remediation; wells;     Show all 7 Subjects
Abstract:
... A new semi-analytical solution to study groundwater flow fields associated with pumping or injection wells in confined isotropic aquifers with uniform regional flow is proposed and tested against steady-state and transient-state numerical simulations on MODFLOW-MODPATH. The solution is based on the complex potential theory and can be used for large numbers of arbitrarily positioned wells operated ...
DOI:
10.1007/s10040-018-1869-0

5. Large deformation of tunnels in longwall coal mines

Author:
Wang, Meng; Zheng, Dongjie; Niu, Shuangjian; Li, Wenfeng
Source:
Environmental earth sciences 2019 v.78 no.2 pp. 45
ISSN:
1866-6280
Subject:
groundwater,   etc   ; coal; deformation; engineering; models;     Show all 5 Subjects
Abstract:
... Large deformation of tunnels in longwall coal mines creates massive cracks in the surrounding rocks, which may cause groundwater loss and threaten the coal mine safety. Rock mechanical characterization is crucial for understanding the large deformation of underground openings. Based on the theoretical analysis and laboratory triaxial tests, this study aims to propose a strength degradation model o ...
DOI:
10.1007/s12665-019-8044-3

6. The application of 0–1 mixed integer nonlinear programming optimization model based on a surrogate model to identify the groundwater pollution source

Author:
Guo, Jia-yuan; Lu, Wen-xi; Yang, Qing-chun; Miao, Tian-sheng
Source:
Journal of contaminant hydrology 2019 v.220 pp. 18-25
ISSN:
0169-7722
Subject:
groundwater contamination,   etc   ; algorithms; kriging; models;     Show all 4 Subjects
Abstract:
... The optimization model is presently used for the identification of pollution sources and it is based on non-linear programming optimization. The decision variables in this model are continuous, resulting in a weak recognition of integer variables including pollution source location. In addition, as the number of pollution sources increase, so the calculated load increases exponentially and accurac ...
DOI:
10.1016/j.jconhyd.2018.11.005

7. The Effect of Hydraulic Gradient and Pattern of Conduit Systems on Tracing Tests: Bench‐Scale Modeling

Author:
Mohammadi, Zargham; Gharaat, Mohammad Javad; Field, Malcolm
Source:
Ground water 2019 v.57 no.1 pp. 110-125
ISSN:
0017-467X
Subject:
groundwater,   etc   ; advection; aquifers; karsts; models;     Show all 5 Subjects
Abstract:
... Tracer breakthrough curves provide valuable information about the traced media, especially in inherently heterogeneous karst aquifers. In order to study the effect of variations in hydraulic gradient and conduit systems on breakthrough curves, a bench scale karst model was constructed. The bench scale karst model contains both matrix and a conduit. Eight tracing tests were conducted under a wide r ...
DOI:
10.1111/gwat.12659

8. Groundwater–lakewater interactions: an evaluation of the impacts of climate change and increased abstractions on groundwater contribution to the Volta Lake, Ghana

Author:
Yidana, Sandow Mark; Vakpo, Evans Kofi; Sakyi, Patrick Asamoah; Chegbeleh, Larry Pax; Akabzaa, Thomas M.
Source:
Environmental earth sciences 2019 v.78 no.3 pp. 74
ISSN:
1866-6280
Subject:
groundwater; groundwater flow; groundwater recharge,   etc   ; aquifers; basins; climate change; irrigation; lakes; models; Ghana;     Show all 10 Subjects
Abstract:
... A 3D steady state groundwater flow model has been calibrated for the Afram Plains portion of the Southern Voltaian Sedimentary Basin. The model was based on data of hydraulic parameters of the aquifer in the area, and regional groundwater recharge estimates conducted by various researchers using a variety of methods. Model calibration was conducted using hydraulic head data of 43 boreholes in the ...
DOI:
10.1007/s12665-019-8076-8

9. Minimization of Transient Groundwater Pumping Cost - Analytical and Practical Solutions

Author:
Katsifarakis, K.L.; Nikoletos, I.A.; Stavridis, Ch.
Source:
Water resources management 2018 v.32 no.3 pp. 1053-1069
ISSN:
0920-4741
Subject:
groundwater; groundwater flow,   etc   ; aquifers; wells;     Show all 4 Subjects
Abstract:
... In this paper, we study pumping cost minimization for any number and layout of wells under transient groundwater flow conditions in infinite confined aquifers and semi-infinite ones, to which the method of images applies. Moreover, we take into account additional steady-state flow, which is independent of the well system and results in non-horizontal initial hydraulic head level distribution. We p ...
DOI:
10.1007/s11269-017-1854-8

10. Numerical model on the application of sand columns in recharge reservoir

Author:
Azis, Akhmad; Badaruddin, Sugiarto; Faisal, Zulvyah; Iqbal, Muh.Taufik; Hasanuddin, Haeril Abdi
Source:
Groundwater for sustainable development 2019 v.8 pp. 368-372
ISSN:
2352-801X
Subject:
groundwater; groundwater extraction; groundwater recharge,   etc   ; aquifers; mathematical models; regression analysis; saltwater intrusion; sand; subsidence; sustainable development; water quality; water shortages;     Show all 12 Subjects
Abstract:
... Excessive groundwater extraction may lead to groundwater depletion and causes land subsidence, sea water intrusion, and groundwater quality degradation. Regarding these problems, it is required to study the sand column placed at the base of the reservoir as an alternative solution to increase the amount of water recharged into the aquifer. In this study, numerical modelling was used to explore the ...
DOI:
10.1016/j.gsd.2018.12.004

11. Biological groundwater treatment for hexavalent chromium removal at low chromium concentrations under anoxic conditions

Author:
Panousi, E.; Mamais, D.; Noutsopoulos, C.; Mpertoli, K.; Kantzavelou, C.; Nyktari, E.; Kavallari, I.; Nasioka, M.; Kaldis, A.
Source:
Environmental technology 2019 v.40 no.3 pp. 365-373
ISSN:
1479-487X
Subject:
groundwater; groundwater contamination; groundwater treatment,   etc   ; anaerobic conditions; biomass; cheese whey; chemical oxygen demand; chromium; environmental technology; milk; nitrates; sugars;     Show all 12 Subjects
Abstract:
... The objective of this work is to evaluate biological groundwater treatment systems that will achieve hexavalent chromium removal from groundwater at hexavalent chromium (Cr(VI)) groundwater concentrations in the 0–200 μg/L range under anoxic conditions. The effect of type of organic substrate added as feed to the groundwater treatment system (milk, sugar and cheese whey), the effect of different c ...
DOI:
10.1080/09593330.2017.1393013

12. Towards a computationally efficient free-surface groundwater flow boundary condition for large-scale hydrological modelling

Author:
Rahman, M.; Rosolem, R.; Kollet, S.J.; Wagener, T.
Source:
Advances in water resources 2019 v.123 pp. 225-233
ISSN:
0309-1708
Subject:
groundwater; groundwater flow; groundwater recharge,   etc   ; base flow; hydrologic cycle; hydrologic models; model validation; rivers; runoff; saturated flow; soil water; watersheds;     Show all 12 Subjects
Abstract:
... Shallow groundwater is a critical component of the terrestrial water cycle. It sustains baseflow in rivers, supplies root zones with soil moisture during dry periods, and directly influences the land-atmosphere exchange processes. Nonetheless, the integration of groundwater into large-scale hydrological models remains challenging. The most detailed way of representing groundwater dynamics is to in ...
DOI:
10.1016/j.advwatres.2018.11.015

13. Adsorption of methyl tert-butyl ether (MTBE) onto ZSM-5 zeolite: Fixed-bed column tests, breakthrough curve modelling and regeneration

Author:
Zhang, Yunhui; Jin, Fei; Shen, Zhengtao; Wang, Fei; Lynch, Rod; Al-Tabbaa, Abir
Source:
Chemosphere 2019 v.220 pp. 422-431
ISSN:
0045-6535
Subject:
groundwater,   etc   ; adsorption; dose response; hydrophobicity; models; zeolites;     Show all 6 Subjects
Abstract:
... ZSM-5, as a hydrophobic zeolite, has a good adsorption capacity for methyl tert-butyl ether (MTBE) in batch adsorption studies. This study explores the applicability of ZSM-5 as a reactive material in permeable reactive barriers (PRBs) to decontaminate the MTBE-containing groundwater. A series of laboratory scale fixed-bed column tests were carried out to determine the breakthrough curves and eval ...
DOI:
10.1016/j.chemosphere.2018.12.170

14. Your work is my boundary condition! Challenges and approaches for a closer collaboration between hydrologists and hydrogeologists

Author:
Staudinger, Maria; Stoelzle, Michael; Cochand, Fabien; Seibert, Jan; Weiler, Markus; Hunkeler, Daniel
Source:
Journal of hydrology 2019
ISSN:
0022-1694
Subject:
groundwater,   etc   ; models; preserves; surface water; watersheds;     Show all 5 Subjects
Abstract:
... Hydrologists and hydrogeologists both study the flux and storage of water with the numerous interactions and feedback mechanisms of surface water and groundwater. Traditionally however, focus, models and scales of the studies differ. With this commentary, situations should be illustrated in which the boundary conditions that each discipline assumes, preserves and actively uses, can and have to be ...
DOI:
10.1016/j.jhydrol.2019.01.058

15. Combined recharge: A method to prevent ground settlement induced by redevelopment of recharge wells

Author:
Zeng, Chao-Feng; Zheng, Gang; Xue, Xiu-Li; Mei, Guo-Xiong
Source:
Journal of hydrology 2019 v.568 pp. 1-11
ISSN:
0022-1694
Subject:
groundwater recharge,   etc   ; dewatering; soil movement; wells;     Show all 4 Subjects
Abstract:
... Artificial recharge is an effective way to minimize dewatering-induced ground settlements in deep excavation. To ensure the success of a long-term recharge, it is necessary to redevelop recharge wells (i.e., pumping) periodically to prevent well clogging. Field measurements show that ground settlements will occur during the well redevelopment. This paper proposed a method referred to as the combin ...
DOI:
10.1016/j.jhydrol.2018.10.051

16. Riesenkampf's vortex solution revisited for 2-D commingling of groundwater in a three-layered aquifer: Vertical-inclined-horizontal seepage in aquitard

Author:
Kacimov, A.R.; Al-Maktoumi, A.
Source:
Advances in water resources 2019 v.123 pp. 84-95
ISSN:
0309-1708
Subject:
groundwater,   etc   ; aquifers; hydrologic models; seepage; topology;     Show all 5 Subjects
Abstract:
... Using exact and explicit analytical solutions and MODFLOW simulations we show that downstream of an unconformity (transition from an aquifuge layer to a homogeneous aquitard) groundwater seeps at varying angles with respect to the layering. As a generalization of the Anderson (2003) two-layered composite, a steady, 2-D Darcian flow in a three-layered aquifer is studied. This flow is generated by d ...
DOI:
10.1016/j.advwatres.2018.11.007

17. The value of simplified models for spin up of complex models with an application to subsurface hydrology

Author:
Erdal, Daniel; Baroni, Gabriele; Sánchez-León, Emilio; Cirpka, Olaf A.
Source:
Computers & geosciences 2019 v.126 pp. 62-72
ISSN:
0098-3004
Subject:
groundwater; groundwater recharge,   etc   ; computers; hydrologic models; mathematical models; seasonal variation; spinning; vadose zone; water table;     Show all 9 Subjects
Abstract:
... Spinning up large-scale coupled surface-subsurface numerical models can be a time and resource consuming task. If an uninformed initial condition is chosen, the spin-up can easily require 20 years of repeated simulations on high-performance computing machines. In this paper we compare the classical approach of starting from a fixed shallow depth to groundwater (here 3 m) with three more informed a ...
DOI:
10.1016/j.cageo.2019.01.014

18. Relationships between urban aquifers and preserved areas south of Mexico City

Author:
Canteiro, Marcelo; Olea, Selene; Escolero, Oscar; Zambrano, Luis
Source:
Groundwater for sustainable development 2019 v.8 pp. 373-380
ISSN:
2352-801X
Subject:
groundwater; groundwater extraction,   etc   ; aquifers; green infrastructure; rain; sustainable development; urbanization; water flow; water management; Mexico;     Show all 10 Subjects
Abstract:
... Mexico City is an example of intense socio-ecosystem interactions, particularly in water management. The groundwater under this city has complex structures and dynamics due to the coexistence of aquifers located at different depths. Through groundwater extraction, the main aquifer supports 71% of the water demand of the city. In this research, we describe the dynamics between aquifers and the surf ...
DOI:
10.1016/j.gsd.2018.12.007

19. Slow-release permanganate versus unactivated persulfate for long-term in situ chemical oxidation of 1,4-dioxane and chlorinated solvents

Author:
Evans, Patrick J.; Dugan, Pamela; Nguyen, Dung; Lamar, Michael; Crimi, Michelle
Source:
Chemosphere 2019 v.221 pp. 802-811
ISSN:
0045-6535
Subject:
groundwater; groundwater flow,   etc   ; aquifers; dioxane; longevity; mass transfer; oxidants; oxidation; silt; soil; solvents;     Show all 11 Subjects
Abstract:
... The objective of this research was to evaluate slow-release permanganate and unactivated persulfate for in situ treatment of dioxane and associated chlorinated solvents. Laboratory batch studies with unactivated persulfate in deionized water or in soil and groundwater demonstrated dioxane removal with pseudo second-order rate constants ranging from 10−5 to 10−3 M−1 s−1. Flow-through column studies ...
DOI:
10.1016/j.chemosphere.2019.01.075

20. Uncertainties in tritium mass balance models for groundwater recharge estimation

Author:
Li, Zhi; Jasechko, Scott; Si, Bingcheng
Source:
Journal of hydrology 2019 v.571 pp. 150-158
ISSN:
0022-1694
Subject:
groundwater; groundwater recharge,   etc   ; aquifers; models; risk assessment; soil water; tritium; uncertainty; vadose zone; China;     Show all 10 Subjects
Abstract:
... Understanding the time that water takes to traverse the vadose zone is important to quantify groundwater recharge rates and to assess the vulnerability of aquifers to contamination. Tritium mass balance models provide measurement-driven estimates of soil water velocities, yet uncertainties embedded in these groundwater recharge estimates are rarely investigated. Here we analyze six >15-m tritium p ...
DOI:
10.1016/j.jhydrol.2019.01.030