7/25/2019 IBIBAZO
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IPRC KIGALI
CIVIL ENGINEERING DEPARTMENT
WATER AND SANITATION PROGRAM
YEAR III
GROUNDWATER ENGINEERING ASSIGNMENT I. (6 GROUPS)
1.
i. Discuss briefly as to how the water is stored into the
groundwater reservoir. Briefly
mention the various zones and importance of the 'zone of
saturation' in this connection.
ii. Explain the differences between the processes by which water
is released from storage
when groundwater is abstracted from a confined aquifer and an
unconfined aquifer.
2.
Define and explain the following terms, as used in connection
with groundwater:
i. Capillary fringe
ii. Specific yield and Field capacity
iii. Permeability and transmissibility
iv. Aquifers, aquitards, aquifuge and aquicludes
v. Perched- aquifers
vi. Storage coefficient of an aquifer
vii. Specific capacity of wells
viii. Well loss.
ix.
Vadose waterx. Pellicular water
xi. Infiltration wells and infiltration galleries.
3. A well in an unconfined aquifer is pumped over a long period
at a rate of 0.05 m3/s until
approximate steady-state conditions are achieved. Two
observation wells at distances of
25 m and 50 m from the abstraction well give observed drawdowns
below the initial
water table level of 15.3 m and 9.5 m respectively. If the
saturated thickness of the
aquifer prior to pumping is 80 m, determine the hydraulic
conductivity of the aquifer
material.
4. The following drawdown data were obtained from a pumping test
performed on a
confined sandy aquifer. Determine the transmissivity and storage
coefficient using
Jacobs equation above; if the pumping rate was constant at 200
liter/sec and the
drawdown data were obtained from an observation well located 800
m from the
abstraction well.
