1. Answer : (a) Foul smell
Explanation: Foul smell is a quality of waste water.
2. Answer : (a) water for life
Explanation: Period 2005-2015 is being celebrated as the international decade for action on water for life.
3. Answer : (b) 50-60 m
Explanation: Manholes are located at every 50-60 m in the sewerage, at the junction of two or more sewers and at points where there is a change in direction.
4. Answer : (b) aerobic bacteria
Explanation: Sludge is collected by a scrapper. It is transferred to a separate tank where it is decomposed by the anaerobic bacteria. The biogas produced in the process can be used as fuel.
5. Answer : (a) Earthworm
Explanation: In Vermi-processing toilets, humans excreta is treated by earthworms. In this process, human excreta is completely converted to vermi cakes by earthworms.
6. Answer : (a) liquid waste
Explanation: Sewage is defined as waste water due to which it is a liquid waste.
7. Answer : (c) Both Biogas and sludge
Explanation: Biogas and sludge are the products of wastewater treatment.
8. Answer : (d) All of these
Explanation: A Open drain systems are a breeding place for different flies, mosquitoes, and other disease causing organisms. The waste drainage system should be closed.
9. Answer : (a) Sewers
Explanation:The pipes through which the wastewater flows into the sewage are known as sewers, whereas, wastewater is collected into the sewage from homes, industries and hospitals. Hence, sewers is not a source of wastewater.
10. Answer : (d) Water coming out of a laundry
Explanation: This water is called as wastewater. Water coming out of the damaged tap, water coming out of shower and water flowing in a river are not dirty hence water coming out of a laundry.
11. Answer : (b) wastewater
Explanation: Wastewater is used water that has been affected by domestic, industrial and commercial use. Wastewater effluents are released to a variety of environments, such as lakes, ponds, streams, rivers, estuaries and oceans. Wastewater also includes storm runoff, as harmful substances wash off roads, parking lots and rooftops
12. Answer : (b) health hazard
Explanation: Untreated human excreta is a health hazard. It contains various disease-causing microorganisms. When this contaminated water is used for drinking, it causes diseases such as cholera, typhoid, hepatitis, dysentery, etc, which may even lead to death.
13. Answer : (d) Cow dung
Explanation: The gas produced from cow dung or other organic material is called biogas. Biogas is a gas produced from the fermentation process of organic materials.
14. Answer : (d) sand and grit removal
Explanation: Grit removal is the process used to remove sand, silt and grit from water. Grit (and sand) removal is often found in the headworks of wastewater treatment plants.
15. Answer : (b) biogas plant
Explanation: In many villages, human excreta from the toilet seats in the homes flows directly into biogas plant through covered drains . The biogas produced is used as a fuel.
16. Answer : (a) Municipal corporation
Explanation: The urban poor suffer disproportionately from the lack of adequate sanitation. .Studies have shown that improved health outcomes are dependent on neighbours' access to adequate sanitation.
17. Answer : (a) cleaning of water
Explanation: Cleaning of water is a process of removing pollutants before it enters a water body or is reused. This process of wastewater treatment is commonly known as Sewage Treatment.
18. Answer : (c) energy
Explanation: Biogas is a mixture of gases, primarily consisting of methane and carbon dioxide, produced from raw materials such as agricultural waste, manure, municipal waste, plant material, sewage, green waste and food waste. It is a renewable energy source.
19. Answer : (c) Phosphates
Explanation: Phosphate or phosphorus is an inorganic component and hence, it is considered an inorganic impurity in sewage.Urea, pesticides, and vegetable waste all are organic.
20. Answer : (a) aerobic bacteria
Explanation: Aerator. Air is pumped into the clarified water to help aerobic bacteria to grow. Bacteria consume human waste, food waste, soaps and other unwanted matter still remaining in clarified water.
21. Answer : (b) Sewage
Explanation: Sewage is liquid waste containing dissolved impurities called as contaminants. Sewage comprises dissolved and suspended impurities.
22. Answer : (b) Waste Water Treatment Plant
Explanation: A wastewater treatment plant is a facility in which a combination of various processes (e.g., physical, chemical and biological) are used to treat industrial wastewater and remove pollutants.
23. Answer : (c) They harden and block the pipe
Explanation: Cooking oil should not be thrown down the drain because it can block the drainage pipes. The fats clog the soil pores which reduces its effectiveness in filtering water and therefore blocks the drain pipes.
24. Answer : (d) Cholera
Explanation: Cholera, like other waterborne diseases, can spread if food and, in particular, water become contaminated with the stools of an infected person.
25. Answer : (c) Organic
Explanation: It defines biodegradable waste as “any waste that is capable of undergoing anaerobic or aerobic decomposition, such as food and garden waste, and paper and cardboard.”
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