SECTION – B
5.
Answer any FOUR sub-parts not exceeding150 words
for each sub-part:
(a)
(i) A wall penetrating into an unconfined
aquifer having a saturated thickness of 100 meter. The discharge is 250 lit /
min at 12m draw down. Assuming equilibrium flow conditions and a homogeneous
aquifer, estimate discharge at 18 m draw down. The distance from the well where
the draw down influence is not appreciable may be taken to be equal for both
the cases.
(iii)
Define following terms:
(1)
Semi-confined.
(2)
Perched aquifer
(3)
Unconfined aquifer.
(b)
Explain different types of irrigation
efficiencies used to evaluate irrigation water management practices.
(c)
(i) In a
tile drainage system used for an irrigated area, tile drains of 0.2m dia are to
be used. The depth for the drains is 2 m below the soil surface. Hydraulic
conductivity of his soil is 1 m/ day (uniform). The area is irrigated once in
15 days and it is estimated that the losses are 30mn in 15 days so that the
average discharge of the drainage system is 2 mm/day. Calculate the required
drain spacing if the water table is to be
kept at 1.5m from the ground
surface (take S= 80m for d = 4m and equivalent depth= 3.55 m)
(d)
Discuss briefly the design principles involved
in the design of a strainer type of a tube well.
(e)
(i) What are the sources of water supply to
farmsteads?
Mention the criteria to be considered while designing a storage tank.
(i)
Determine size of an overhead water tank for a
farmstead demanding a maximum of about 40,000 lit, of water per hour for 3
hours during noon and only about 30,000 lit, per hr. During rest of the period. The tube well is
capable of supplying at the rate on only 25,000 lit/hr.
6.
(a) Write down few conditions where sprinkler
can be used advantageously. Specify its advantages over surface irrigation
methods and also list out its limitation.
(b) Write short notes on:
(i)
Silos
(ii)
Bukhari
(iii)
Surkhi
(iv)
Curing
(v)
Finishing
(vi)
Morai.
7.
(a) Eight grams sodium chloride has been
dissolved in 4 lit. Of water. Express the salt concentration in ppm, in ohms,
millimhos, micromhos/ cm and m eq/it.
(b) What are the methods recommended for reclamation of alkali and saline
soils?
(C) Explain various causes of water logging and mention approacheers to
solve the drainage problems of a location.
(d) Write short notes on:
(i)
Drainage Coefficient.
(ii)
Exchangeable sodium.
8.
(a) Describe the principle of operation of
centrifugal pumps and list out few common troubles while operating the pumps.
(b) Differentiate between:
(i)
Shallow tube well and deep tubewell.
(ii)
Infiltration and percolation
(iii)
Specify storage and storativity.
(iv)
Hydraulic conductivity and intrinsic
permeability
(v)
Aquiclude and aquitard.
