An Analysis of Groundwater Levels Surrounding Jungyeong Tunnel Using Visual-MODFLOW

For effective groundwater management of a basin, it is essential that a careful water balance study be carried out. A three-dimensional transient-state finite difference groundwater flow model is used to quantify the groundwater fluxes and analyze the dynamic changes of groundwater level. After monitoring groundwater levels for 43 typical observation wells through a simulation study of the groundwater flow model with a depth of 300 m, results reveal that the study area has a lateral recharge of about 3.57 × 109 m3, which makes up 79.08% of the total recharge; total evaporation is about 1.81 × 108 m3, which makes up 3.77% of the total discharge. The balance of groundwater is negative, with a recharge and discharge difference of −2.81 × 108 m3. The correlation coefficient between the observed head and the calculated head for the simulation period is greater than 0.81, indicating the simulation results are satisfactory. The maximum groundwater drawdown is 26.59 m and the rate of the groundwater drawdown is 0.15 m/d during normal operation of the pumping well.

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Envisaging the Sustainability of an Aquifer by Developing Groundwater Flow Model for a Part of ChoutuppalMandal, Nalgonda District, Telangana, India

Nepal Journal of Science and Technology ◽

10.3126/njst.v19i1.29824 ◽

2020 ◽

Vol 19 (1) ◽

pp. 222-233

Author(s):

P. K. Neupane ◽

N. C. Mondal ◽

A. Manglik

Keyword(s):

Drinking Water ◽

Groundwater Flow ◽

Flow Equation ◽

Visual Modflow ◽

Fractured Aquifer ◽

Pumping Rate ◽

Groundwater Levels ◽

The North ◽

Weathered Layer ◽

Nalgonda District

Recurring droughts and increased exploitation of groundwater to meet the growing water needs have resulted in the decline of regional groundwater level and dry, weathered zone in a part of the Choutuppal Mandal, Nalgonda district, Telangana, India. A groundwater model has been developed using an inventory of 20 observation wells for future pumping schemes to evolve a classic interface (Build: 4.6.0.168) of available wells. The developed model has been reviewed using Visual MODFLOW, and a base map is prepared for the sub-surface structure. The area spreading about 0.43 km2is conceptualized as a two-layered model consisting of a weathered layer overlying a fractured aquifer. The model has been digitized into grids of 5m×5m in each layer. The integrated finite difference method has been utilized to discretize the groundwater flow equation and simulate groundwater flow with the help of calculated parameters along with the boundary conditions and acting stresses. Results show that the computed groundwater levels are in good agreement with the observed heads, and groundwater is flowing from the South to the North direction. The estimated velocities vary from 0.01 to 1.95 m/d. The optimum pumping schemes have also been simulated up to the year 2022. It has been observed that the maximum pumping rate should not go beyond 24m3/day. Since the drinking water demand(10-15m3/day) in the study site is below this limit, it can be inferred that the aquifer will sustain and provide enough drinking water.

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The Effect of Coal Mining on the Multi-Aquifer System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.919-921.1252 ◽

2014 ◽

Vol 919-921 ◽

pp. 1252-1256

Author(s):

Jun Qin Lei ◽

Xiu Qing Zheng ◽

Hong Fei Zang

Keyword(s):

Coal Mining ◽

Three Dimensional ◽

Vertical Direction ◽

Shanxi Province ◽

Visual Modflow ◽

Limestone Aquifer ◽

Ordovician Limestone ◽

Aquifer System ◽

Groundwater Levels ◽

Groundwater Aquifer

Based on the analysis of the regional geological and hydrogeologic conditions of a coal mine in Xishan Coalfield, Shanxi Province in China, the groundwater aquifer system is generalized as a three layers structure in vertical direction and a three-dimensional unsteady flow model in confined aquifer is established. The regime of karst groundwater levels under the coal mining conditions for both Carboniferous and Ordovician limestone aquifers are predicted by using Visual Modflow. The results show that the groundwater levels of the two aquifers are all in decline as a result of coal mining. After 2373 days of mining, the maximum drawdown is 137m in Carboniferous limestone aquifer with the unwatering area in southeast, while the water level in Ordovician limestone aquifer dropped by 8.1m. The dropped rates of groundwater levels in the two aquifers trend to decrease with the coal mining. The results play an important role in the reasonable protection of water resources.

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ALGORITHM FOR MANAGEMENT AND PROTECTION OF SUBMERSIBLE PUMP

International Conference on Technics Technologies and Education ◽

10.15547/ictte.2019.04.035 ◽

2019 ◽

pp. 245-250

Author(s):

Tanya Pehlivanova

Keyword(s):

Global Warming ◽

Submersible Pump ◽

Groundwater Levels ◽

Frequent Switching ◽

Full Utilization ◽

Level Sensors

Global warming has led to lower levels of the water basins. Groundwater levels also decrease. Sometimes they fall so much so that submersible pumps in the wells remain almost dry and even in short work cycles get damaged. Their repairs are very expensive and labour intensive. An algorithm for management and protection of submersible pump is proposed in the paper. It uses 5 level sensors. It allows full utilization of the wells capacity and protects the pump motors from premature wear due to frequent switching on and off.

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Using groundwater levels and Specific Yield to Estimate the Recharge, South of Erbil, Kurdistan Region, Iraq

Academic Journal of Nawroz University ◽

10.25007/ajnu.v7n4a289 ◽

2018 ◽

Vol 7 (4) ◽

pp. 191

Author(s):

Sherwan Sh. Qurtas

Keyword(s):

Unconfined Aquifer ◽

Middle Part ◽

Water Levels ◽

Specific Yield ◽

Aquifer System ◽

Groundwater Levels ◽

Monitoring Wells ◽

Water Table Fluctuation Method ◽

Recharge Estimation ◽

Fluctuation Method

Recharge estimation accurately is crucial to proper groundwater resource management, for the groundwater is dynamic and replenished natural resource. Usually recharge estimation depends on the; the water balance, water levels, and precipitation. This paper is studying the south-middle part of Erbil basin, with the majority of Quaternary sediments, the unconfined aquifer system is dominant, and the unsaturated zone is ranging from 15 to 50 meters, which groundwater levels response is moderate. The purpose of this study is quantification the natural recharge from precipitation. The water table fluctuation method is applied; using groundwater levels data of selected monitoring wells, neighboring meteorological station of the wells, and the specific yield of the aquifers. This method is widely used for its simplicity, scientific, realistic, and direct measurement. The accuracy depends on the how much the determination of specific yield is accurate, accuracy of the data, and the extrapolations of recession of groundwater levels curves of no rain periods. The normal annual precipitation there is 420 mm, the average recharge is 89 mm, and the average specific yield is around 0.03. The data of one water year of 2009 and 2010 has taken for some technical and accuracy reasons.

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