THEORY EXAMINATION (SEM–VIII) 2016-17 GROUNDWATER MANAGEMENT

SECTION – A

Explain the following (Short Answer Type)

Aquifers are underground layers that store groundwater. Types include confined aquifers, unconfined aquifers, semi-confined aquifers, and perched aquifers.

A hydro-geologist is a scientist who studies groundwater movement, distribution, and quality in soil and rocks.

Dupuit’s theory assumes that groundwater flow is horizontal, uniform, and steady, ignoring vertical flow components.

Confined aquifers are enclosed between impermeable layers and contain pressurized water, while unconfined aquifers have an open upper surface and water table.

A water well is a structure used to extract groundwater from underground aquifers.

Types of tube wells include shallow tube wells, deep tube wells, cavity tube wells, and artesian tube wells.

Groundwater modelling techniques include mathematical modelling, physical modelling, and computer-based simulation methods.

Groundwater drainage is the process of removing excess groundwater to control waterlogging and improve soil conditions.

Groundwater management models help in efficient planning, sustainable use, and preventing over-extraction of groundwater resources.

Remote sensing helps in groundwater management by identifying water sources, monitoring water levels, and mapping aquifers.

Questions (Section A)

List types of aquifers.

Who is a hydro-geologist?

Differentiate confined and unconfined aquifers.

What is groundwater drainage?

What is the role of remote sensing?

SECTION – B

Attempt any five (Long Answer Type)

Groundwater occurs due to infiltration of rainwater into soil and rocks, forming aquifers below the earth’s surface.

Flow nets represent groundwater movement using streamlines and equipotential lines, helping analyze flow patterns.

Well losses occur due to friction, turbulence, and resistance near well openings.

Tube well design considers yield requirements, aquifer thickness, permeability, and drawdown levels.

Well construction involves drilling, casing, and screen installation, while completion includes cleaning and testing the well.

Artificial recharge adds water to aquifers using recharge wells, while artificial discharge removes groundwater using pumping systems.

Groundwater budgeting calculates water inflow and outflow to manage water resources efficiently.

Rainwater harvesting collects and stores rainwater for groundwater recharge in urban areas.

Questions (Section B)

Explain occurrence of groundwater.

What is flow net construction?

What are well losses?

What is artificial recharge?

Explain rainwater harvesting.

SECTION – C

Attempt any two (Detailed Explanation)

Steady-state discharge from a well in an unconfined aquifer can be derived using Darcy’s law, considering assumptions of uniform flow and steady conditions.

Geophysical exploration techniques include electrical resistivity method, seismic method, and magnetic method used to locate groundwater sources.

The hydrologic cycle describes the continuous movement of water through evaporation, condensation, precipitation, infiltration, and runoff.

Contaminated groundwater movement occurs due to diffusion, dispersion, and chemical reactions.

Groundwater modelling uses mathematical and computer-based methods to simulate groundwater flow, while GIS helps analyze spatial groundwater data.

Questions (Section C)

What is hydrologic cycle?

Explain groundwater modelling.

What are geophysical exploration techniques?