
Civil Engineering MCQ. PWD, CPWD, RRB, SSC, Mock Test Paper
Subject: Environmental Engineering 9
Part 3: List for questions and answers of Environmental Engineering II
Q1.Presence of __________ hardness is responsible for the temporary hardness in water.
a) Carbonate
b) Calcium
c) Chloride
d) Sulphate
Q2.A shallow pond in which the sewage is retained and biologically treated is called
a) Oxidation
b) Imhoff tank
c) Lagoon
d) Skimming tank
Q3.Which is the most practical and economical method for removal of suspended solid matter from polluted water?
a) Sedimentation
b) Skimming off
c) Chlorination
d) Biological oxidation
Q4.Atmospheric pollution caused by the exhaust gas of supresonic transport air-crafts is mostly in the atmospheric region called
a) Thermosphere
b) Stratosphere
c) Troposphere
d) Mesosphere
Q5.Iron and manganese present in the polluted water is removed by
a) Simple filtration
b) Oxidation followed by settling, filtration
c) Chemical coagulation
d) Chlorination only
Q6.The clarigesters are
a) Circular septic tanks
b) Rectangular septic tanks
c) Circular Imhoff double tanks with bottom hoppers
d) Circular Imhoff double storey tanks without bottom hoppers
Q7.Rate of flow of sewage is generally assumed
a) More than the rate of water supply
b) Equal to the rate of water supply
c) Less than the rate of water supply
d) At 150 litres per capita.
Q8.The gradient of sewers depends upon
a) Velocity of flow
b) Diameter of the sewer
c) Discharge
d) All the above
Q9.The drop man holes are generally provided in sewers for
a) Industrial areas
b) Large town ships
c) Hilly town ships
d) Cities in plains
Q10.A drop manhole is provided if
a) A sewer drops from a height
b) A branch sewer joins the main sewer at higher level
c) A lamp is inserted to check obstruction
d) None of these
Q11.In a city the ratio of the drainage to sewage is 20, the percentage discharge passing through non-monsoon periods, is
a) 5
b) 10
c) 15
d) 20
Q12.The standard B.O.D. of water is taken for
a) 2 days
b) 3 days
c) 5 days
d) 10 days
Q13.Pick up the correct statement from the following:
a) The black colour indicates septic sewage
b) The fresh sewage is practically odourless
c) The sewage omits offensive odours after four hours
d) All the above.
Q14.A sewer running partially full and hurried with back filled fails in compression due to
a) Weight of the pipe
b) Weight of the back fill
c) Superimposed traffic loads
d) All the above.
Q15.A manhole is classified as shallow if its depth is between
a) 0.5 to 0.7 m
b) 0.7 to 0.9 m
c) 0.9 to 1.20 m
d) 1.2 to 1.50 m
Q16.The detention period for plain sedimentation water tanks, is usually
a) 4 to 8 hours
b) 8 to 16 hours
c) 16 to 24 hours
d) 24 to 36 hours
Q17.Fresh sewage may become stale in
a) Two to three hours
b) Three to four hours
c) Six hours.
d) Ten hours.
Q18.The small sewers are cleaned by
a) Flushing
b) Cane rodding
c) Wooden pills
d) None of these
Q19.Dry water flow in a combined sewer, is
a) Industrial sewage
b) Domestic sewage
c) Storm water
d) Inclusive of domestic and industrial sewage but excludes storm water.
Q20.For detecting the nitrates in sewage, the colour may be developed by adding
a) Potassium permanganate
b) Sulphuric acid and napthamine
c) Phenol-di-sulphuric acid and potassium hydroxide
d) None of these
Part 3: List for questions and answers of Environmental Engineering II
Q1. Answer: b
Q2. Answer: a
Q3. Answer: a
Q4. Answer: b
Q5. Answer: b
Q6. Answer: d
Q7. Answer: d
Q8. Answer: d
Q9. Answer: c
Q10. Answer: b
Q11. Answer: d
Q12. Answer: c
Q13. Answer: d
Q14. Answer: d
Q15. Answer: b
Q16. Answer: a
Q17. Answer: b
Q18. Answer: a
Q19. Answer: c
Q20. Answer: c