Environmental Engineering – Multiple Choice Questions (MCQs)

1. 61. The "National Ambient Air Quality Standards (NAAQS)" specify:

   • A. Maximum permissible levels of air pollutants
   • B. Minimum levels of air pollutants
   • C. Average levels of air pollutants
   • D. Ideal levels of air pollutants

2. 62. What is "Groundwater Recharge"?

   • A. Pumping water out of the ground
   • B. The process by which water moves downward from surface water to groundwater
   • C. Building dams
   • D. Creating artificial lakes

3. 63. The term "water table" refers to:

   • A. The surface of the ocean
   • B. The top of the saturated zone in an aquifer
   • C. The depth of a well
   • D. The level of water in a river

4. 64. What is "Arsenic Contamination" in groundwater?

   • A. Presence of arsenic in air
   • B. Presence of excessive arsenic in groundwater
   • C. Presence of arsenic in soil
   • D. Presence of arsenic in plants

5. 65. Which treatment method is effective for removing arsenic from water?

   • A. Chlorination
   • B. Aeration
   • C. Adsorption using activated alumina
   • D. Filtration

6. 66. What is "Defluoridation"?

   • A. Adding fluoride to water
   • B. Removing fluoride from water
   • C. Measuring fluoride levels
   • D. Storing fluoride

7. 67. The "pH" of ideal drinking water is typically around:

   • A. 3
   • B. 5
   • C. 7
   • D. 9

8. 68. What is "Alkalinity" of water?

   • A. Its corrosive nature
   • B. Its capacity to neutralize acids
   • C. Its ability to dissolve substances
   • D. Its salt content

9. 69. The "chlorination breakpoint" in water treatment refers to:

   • A. The point at which chlorine becomes ineffective
   • B. The point at which all chlorine demand is met and free residual chlorine begins to appear
   • C. The maximum chlorine dosage
   • D. The minimum chlorine dosage

10. 70. What is the function of "rapid mixing" in a water treatment plant?

    • A. To allow solids to settle
    • B. To quickly disperse coagulants throughout the water
    • C. To filter water
    • D. To disinfect water

11. 71. The "flocculation" process in water treatment aims to:

    • A. Kill bacteria
    • B. Cause small particles to clump together into larger
    • C. heavier flocs
    • D. Remove dissolved gases

12. 72. What is a "service reservoir" in water supply systems?

    • A. A reservoir for treated water near the distribution area
    • B. A reservoir for raw water
    • C. A reservoir for wastewater
    • D. A reservoir for irrigation