Rajasthan Public Service Commission 2016
Paper 70JuniorHydroGeologist

1. It is desirable to use Groundwater than Surface water because:

The temperature and chemical composition of groundwater is nearly constant

Groundwater storage is not seriously affected by short droughts

It is stored by nature through many years of recharge

all of these

2. Groundwater development is discouraged in some areas because:

Underlain rocks have insufficient porosity and permeability to yield much water to wells

TDS content in groundwater is greater than that in surface water

In regions of high precipitation cost of developing wells is higher than the cost of developing small streams

All of these

3. In the vicinity of cities the TDS is higher in precipitation because

The dust and smoke produced by factories

Dissolved gases

There are no TDS in precipitation

The dust and smoke produced by factories and Dissolved urban gases


4. The amount of energy required to evaporate one cubic centimetre of water is

597 calories

1000 calories

1597 calories

100 calories

5. Vadose water is in the vadose zone that includes:

Groundwater and capillary water

Capillary water, soil water and groundwater

Capillary water, gravitational water and soil water

Groundwater, gravitational water and soil water

6. Water table is:

The surface in unconfined material along which the hydrostatic pressure is equal to the atmospheric pressure

The surface separating the capillary fringe from the zone of saturation

Water level surface in wells that tap an unconfined saturated material

All of these

7. Aquitards

are layers of clay and silt that retard water flow underground and act as barriers for groundwater

direct the surface water that seeps down and replenishes aquifers

Both Statement are incorrect

Both Statements are correct

8. Water level fluctuations are due to:

changes in groundwater storage

deformation of aquifers

fluctuations of atmospheric pressure

all of these

9. If there are 10 moles per liter of in water

then the pH of water is 5

then it is pure water

then water contains no dissociated OH- ions

then the Eh of water is 10

10. 63 ppm Mg2+(At wt of Mg=24.32,valency=2)is equal to

5.19 epm

6.7 epm

63 epm

6.3 epm

11. Specific electric conductance of potable subsurface water ranges from

30 to 2000 micromhos

0.055 to 0.5 micromhos

45000 to 55000 micromhos

5.0 to 30 micromhos

12. Water for domestic and industrial uses should have less than 1000 ppm TDS and for agricultural uses less than 3000 ppm TDS.

True

false

about 300,000 ppm

10 and 100 ppm TDS respectively

13. Water that has never been part of hydrosphere is called

Juvenile water

Ice water

Metamorphic water

Connate water


14. A mixture of miscible salt water and fresh water is treated as homogeneous

True

False

only if density does not vary from place to place

is treated as heterogeneous

15. Porosity will be highest for cubical array of

rhombs

spheres

cubes

rectangular sandstones pieces

16. Hydraulic conductivity depends on properties of the fluid as well as characteristics of the medium

Darcy failed to recognise the above fact

Dupuit failed to recognise the above fact

Both Darcy and Dupuit failed to recognise the above fact

Darcy was aware of the above fact

17. Intrinsic permeability is characteristic of the

properties of soil and fluid

properties of soil (medium)

properties of fluid

properties of groundwater

18. <img src='./qimages/4373-18.jpg'>

19. The amount of water used in storage released from a column of aquifer with unit cross section under a unit decline of head is represented as:

K

S

T

A

20. For every meter of fresh water above mean sea level, the thickness of the fresh water lens resting on the salt water is about'

35m

36m

40m

37m

21. The rocks generally have distinctive porosity and permeability and for that a geologist during exploration of subsurface water first seeks help by utilizing

petrography

drilling

seismic methods of exploration

magnetic methods of exploration

22. Total water available for recharge, ease of recharge and quantity of groundwater discharge at the surface is determined by

Hydrologic methods of prospecting

Dowsing

Geological maps

Atmospheric analysis

23. The average permeability of igneous and plutonic rocks with depth will generally

increase

decrease

not change

highly increase

24. Difference in yield in wells of igneous and metamorphic rock aquifers is because of

differences of mineralogy

differences in degree of weathering

differences in degree of compaction

None of these

25. Pathological organisms will move efficiently in alluvial aquifers if

soil is thin or absent over water bearing aquifers

wells are unprotected

there is storm runoff in wells

all of these

26. In volcanic rock aquifers, following rocks will generally have high porosity but very low permeability

Basalts

Tuffs

Dike rocks

Intrusives

27. In Cenozoic sediments the salinity of connate water is

less than that of sea water

more than that of sea water

equal to the sea water

less than that of meteoric water

28. The reduction of artesian pressure in valley deposits will induce

expansion of aquifers

compaction of aquifers

compaction of aquifers and adjacent silts and clays

expansion of aquifers and adjacent silts and clays

29. Chemical character of groundwater in large valleys of tectonic origin will generally be

highly variable

the same

always free of salinity induced from ancient sea water

always free of evaporitic solutions

30. The greatest danger of organic pollution is

in areas of extremely permeable auifers

in areas of improper wastedisposable facilities

not a problem in wells within large valleys

all of these

31. What type of water bearing material has the most uniform hydrogeologic properties

sandstone

conglomerate

evaporite

dune sand (Consolidated)

32. The average chemical quality of groundwater is poorer in desert regions because

slow circulation of ground water will slow the flushing of connate water

salt contained in rain will get concentrated at the surface

fine dust in soluble salts blown from plays

all of these

33. Varying electrode spacing in resistivity survey helps in

vertical investigation of an aquifer

noting changes in quality of groundwater

knowing impermeable formations

all of these

34. The ground around electrodes during resistivity survey is moistened to

establish proper contact with earth

to break the conductivity

decrease the salinity of the ground

None of these

35. The subsurface salt water boundaries become apparent on a resistivity depth curve due to
increase in resistivity

decrease in resistivity

straightening of the curve

refraction of the curve

36. Seismic waves may be reflected or refracted

at interface where a velocity change occurs

in homogeneous formations

in groundwater

in ocean water

37. Resistivity Log is affected by

fluid within a well and ground water

character of the surrounding strata

Well diameter

all of these

38. In SP log, flow from the formation into the wells shows

positive values

negative values

no change in values

sharp change in negative values

39. To note water from different aquifers intersected by a well, readings are taken of

SP log

Resistivity log

Temperature log

Calliper log

40. Well diameters along a well can be measured with the help of

Calliper log

Neutron log

Temperature log

Resistivity log

41. Tracer–techniques are adopted to note

Ground water velocity

Ground water quality

Ground water occurrence

Ground water permeability

42. Which is used in Radioactive logs

Neutron rays

gamma particles

Both Gamma particles and neutron rays

all of these

43. the equation h2=W/0.512K(R2-r2)shows depth of salt water at any location is function of

rainfall recharge, size of the island and permeability

rainfall recharge and permeability

rainfall recharge and size of the island

size of the island and permeability

44. Modification in composition of sea water entering an aquifer can occur

by base exchange between water and minerals of aquifer

sulphate reduction, solution and precipitation

by base exchange between water and minerals of aquifer sulphate reduction, solution and precipitation

None of these

45. One of the following does not have significant contribution in establishing hydraulics of ground water.

Henry Darcy

N. Steno

J. Dupuit

A. Theim

46. Initially dry soil that will absorb maximum moisture in contact with atmosphere is called as

wilting point

capillary fringe

hygroscopic coefficient

moisture point

47. Soil moisture is measured by Neutron Scattering based on the fact that fast neutrons are slowed by collisions with

hydrogen

oxygen

chlorine

water

48. As per Darcy’s law Flow rate through porous media is

inversely proportional to head loss

not in accordance with hydraulic gradient

proportional to flow path length

None of these

49. The Water which results due to mixing of fresh water and sea water is

Saline Water

Alkaline Water

Brakish Water

Acidic Water

50. Permeability K is expressed as that shows K has dimensions of

velocity

area

acceleration

gravity

51. <img src='./qimages/4373-51.jpg'>

permeability from a pumped well

porosity from a pumped well

permeability from nonpumping well

transmissivity from nonpumped well

52. This equation h0-h=114.6Q/T W(u),where is called as well fuction. the argument is given by

u=1.87r2S/Tt

u=2.8r2S/Tt

u=3.87r2S/Tt

u=4.87r2S/Tt


53. The resistivity of Fresh water is around ‘20 ohm m’, its conductivity therefore should be about

500 Seimens/cm

500 microS/cm

500 microS/meter

500 microS/feet

54. The units of Yield, Transmissivity and draw down are

m3/s,m2/s and m respectively

m2/s,m2/s and m respectively

m3/s,m2/s and m2 respectively

and m respectively

55. Magnetic resonance sounding method for ground water exploration has many advantages such as: it is only geophysical method that is capable of estimating permeability but has disadvantage such as:

not suitable for volcanic rocks

it is sensitive to power lines, pipes, fences

the maximum depth which can be reached to detect an aquifer layer is 150m.

all of these

56. Diseases which can spread through ground water are

typhoid cholera and Hypertension

typhoid,amoebic dysentery and diabetes

typhoid, amoebic dysentery infectious hepatitis and malaria

typhoid, cholera, amoebic dysentery and infectious hepatitis

57. The acceptable concentration of fluoride in drinking water is about:

1.5 mg/L.

1.5 g/L

1.5 mg/L

1.5 Kg/L

58. The acceptable level as defined by WHO for maximum concentrations of arsenic in safe drinking water is

0.01 mg/L.

0.10 mg/L

1.00 mg/L

0.01 g/L

59. Arsenic contamination of the groundwater in Bangladesh around Ganga Delta is a serious problem. It is one of the solutions is:

to tap into deeper groundwater

to tap into shallow groundwater

to tap very shallow groundwater

None of these

60. Fluoride concentration in water can be reduced by using adsorbents such as:

activated charcoal and alumina

bentonite and kaolinite

red mud and rice husk

all of these

61. The ground water problems being faced in Jodhpur are:

Declining water level, over exploitation of groundwater

Fluoride and nitrate pollution

Rising water level, leakage through sewerage system

all of these

62. Roof top rain water harvesting has been made mandatory in state owned buildings of plot size more than

300 sq.m.

500 sq.m

600 sq.m

200 sq.m

63. Tick mark the correct statement

Recharge to aquifer during normal rain fall in Western Rajasthan is inadequate

Major portion of precipitation in Western Rajasthan gets lost as run off

Identification of potential aquifers is still needed in Western Rajasthan

all of these

64. The advantages of watershed development are:

Arrests soil erosion, improves soil moisture and recharges ground water

Reclaims eroded land and reduces flood

Arrests soil erosion, improves soil moisture and recharges ground water and Reclaims eroded land and reduces flood, both are correct

Only Arrests soil erosion, improves soil moisture and recharges ground water, is correct

65. How much of Earth's water is stored in underground aquifiers

Less than 1



9.5

5

66. An area of land that contains a common set of streams and rivers that all drain into a single larger body is called watershed for e.g.,

Mississippi River

Jaisamand Lake

Stream and ocean

all of these

67. Rainfall is the main source of ground water recharge, The average annual rainfall in Western Rajasthan is about

10cm

30cm

100cm

1000mm

68. A confined aquifer has a transmissivity of 40m2/day.the slope of the piezometric surface is 0.25m/km.how much water per day flows through an aquifer per kilometre width of the aquifer?(hint

100m3/day

10m3/day

1m3/day

1000m3/day

69. Radioactive waste disposal can cause ground water pollution. Possible sites for radio active waste disposal are

salt domes and brine aquifers

subterranean cavity created by underground nuclear explosion

deep mines

all of these

70. Ground water contamination due to coal mining is caused by

oxidation of pyrite

formation of sulfuric acid and iron hydroxide

decrease in pH due to sulphate concentration

all of these

71. Baoris and Jhalra's like traditional water bodies of western Rajasthan are

Surface and ground water bodies

Only surface water bodies

Only ground water bodies

None of these

72. Remote Sensing for ground water involves sensing of

energy source and radiation

interaction with targets

atmospheric interaction

all of these

73. Exploration by resistivity method helps in assessing the quality of groundwater because

Resistivity increases with more dissolved solids in water

Distilled water has very high conductivity

Resistivity decreases with increasing amount of ions

Water is not a very good electrolyte

74. Free air correction is applied in gravity method of exploration because

measured value of gravity decrease with the increase in the elevation

measured value of gravity increases with the increase in the elevation

the equation g0=G M/R2 is not correct

isostatic correction is not required in geodetic survey

75. The magnetic minerals such as magnetite, ilmenite, pyrrhotite etc locally influences the Earth’s field depending upon a factor called

dielectric constant

conductivity

permeability

resistivity

76. The variation in the velocity of elastic seismic waves is dependent upon the rock type and its degree of consolidation therefore

their velocity will not vary for the same rock type such as shale

their velocity will vary for the same rock type such as shale

their velocity will not vary for the same rock type such as granite

their velocity will not vary for the same rock type such as sandstone

77. To determine accurate depth of the beds especially to locate structural traps for ground water, the exploration method employed is

electromagnetic method

gravity method

seismic reflection method

magnetic method

78. Mark the true statement

compressed air is used in pneumatic drills

percussion drill can not be used for making blast holes

hammer drills can not be used as hand held drills

diamond drills are advisable in the soft rock formations

79. Ground penetrating radar(GPR) and seismic reflection techniques are analogous because

both techniques record the time required for a wave to travel to the interface between two formations and then return to the surface

both techniques record the velocity required for a wave to travel to the interface between two formations and then return to the surface

both techniques do not record the time required for a wave to travel to the interface between two formations and then return to the surface

both techniques do not record the velocity required for a wave to travel to the interface between two formations and then return to the surface

80. If the pumping rate is m3/day and the drawdown is 30m

the specific capacity of the well is33.3 m3/day/m

the transmissivity of the well is 33.3 m3/day/m

the storage coefficient of the well is33.3 m3/day/m

All of these

81. For industrial, municipal or irrigation purpose the transmissivity of aquifer should generally be more than

125 m2/day

125 m3/day/m

125 m3/day

225 m2/day

82. The flow of groundwater to the well forms a cone of depression. The volume of cone is

1/3 4pier3h

1/3 pier3

1/3 pier2h

4/3 pier3

83. Groundwater flow velocity can be measured with the help of

Can not be measured

Tracers

dowsing

It remains constant

84. The Flow Net is

A set of intersecting flow lines and equipotential lines

A set of meandering river lines

A set of wind blowing directions

A set of groundwater velocity lines

85. Water having more than 100,000 mg/l T D S is called

Saline water

Brackish water

Brine water

Fresh water

86. Radionuclide contamination in groundwater is measured in

ppm

ppb

pCi/l

gm/l

87. The energy responsible for generating tornadoes and hurricane comes from water because it has

High heat capacity

Highest heat of vaporization

Highest solubility

Quick dissociation

88. The source of Organo-mercury compounds as pollutants in ground water are

Gasoline

Fungicides

Fertilizers

Septic tanks

89. The source of lead in groundwater as pollutant is

Gasoline

Fungicides

Fertilizers

Septic tanks

90. Ozone in the atmosphere is destroyed by

photodissociation by UV rays

reaction with NO

reaction with chlorofluorocarbons

all of these

91. Relative humidity is

amount of water vapour per m2 of air

of maximum amount of water vapour that air can hold

amount of water vapour per m3 of air and of maximum amount of water vapour that air can hold, both are correct

None of these

92. The ocean have an average salinity of 34.77 while fresh water has

0 salinity

salinity of 0.2 to

0.2 salinity

4 salinity

93. Monsoon is the wind system that

never fluctuates

maintains its course in the opposite season

reverses its course in the opposite seasons

has nothing to do with the rotation of the earth

94. Which feature is a sign of Karst Topography

Sinkholes

Artesian Wells

Moraines

Anticline

95. During ice ages the sea level was

5km lower than today

same as today

higher than today

120m lower than today

96. Water is critical in maintaining our uniform body temperature because it has:

High heat capacity

Highest heat of vaporization

Highest solubility

Quick dissociation

97. Water in the atmosphere:

Radiates back heat received from the Sun

Cannot radiate back heat received from the Sun

Has no effect on heat received from the Sun

Makes the Sun look brighter

98. ‘Atmospheric windows’ useful in Remote Sensing are created because

Ozone absorbs UV radiation from the Sun

Carbon dioxide absorbs radiation in the infrared portion of the spectrum

Water vapour absorbs portions of the infrared and microwave radiation

all of these

99. Horizontal permeable conduit for collecting ground water by gravity flow is known as

Tube well

Infiltration gallery

Gravity gallery

Dugwell

100. High amount of Sodium in water (sodium hazard) causes:

Reduction in soil permeability

Hardening of soil

Reduction in soil permeability and Hardening of soil, Both are correct

Only (Hardening of soil) is correct