Extra Questions from Wastewater Story

 

Q 1. What is waste water ?

Ans. 1: Water rich in lather, mixed with oil and black-brown in colour that goes down the drains from sinks, showers, toilets, laundries is dirty. Such water is called wastewater.

Q. 2. What is sewage ? What is the name given to the impurities present in it ?

Ans. 2: Sewage is wastewater released by homes, industries, hospitals, offices and other users. It also includes rainwater that has run down the street during a storm or heavy rain. Moreover, the water that washes off roads and rooftops carries harmful substances with it. Thus, sewage is a liquid waste. 

Most of it is water, which has dissolved and suspended impurities. These impurities are called contaminants.

Q. 3. Describe briefly the network of pipes etc. that acts as a transport system for sewerage.

Ans. 3: In a home or a public building usually one set of pipes brings clean water and another set of pipes takes away wastewater. 

If we could see through the ground, we would see a network of big and small pipes, called sewers, forming the sewerage. It acts as a transport system that carries sewage from the point of being produced to the point of disposal i.e., treatment plant.

Manholes are located at every 50 m to 60 m in the sewerage, at the junction of two or more sewers and also at points where there is a change in direction.

Q. 4. Write a brief note on vermi-processing toilet.

Ans. 4: A design of a toilet in which humans excreta is treated by earthworms has been tested in India. 

It is a novel, low water-use toilet for safe processing of human waste. The operation of the toilet is very simple and hygienic. The human excreta is completely converted to vermi cakes — a resource much needed for soil.

Q. 5. Fill in the blanks :(a) Cleaning of water is a process of removing _______________.
(b) Wastewater released by houses is called _______________ .
(c) Dried _______________ is used as manure.
(d) Drains get blocked by _______________and _______________.

Ans. 5.
(a) Cleaning of water is a process of removing pollutants.
(b) Wastewater released by houses is called sewage.
(c) Dried sludge is used as manure.
(d) Drains get blocked by solid food remains and sanitary towels.

Q. 6. Name a chemical used to disinfect water.

Ans. 6. Chlorine is a chemical that is used for disinfecting water.

Q. 7. Outline your role as an active citizen in relation to sanitation.

Ans. 7: As all know, waste generation is a natural part of human activity. But we can limit the type of waste and quantity of waste produced. Open drains are very common in our localities and they cause highly unhygienic and unsanitary conditions. 

As active citizens we should approach the municipality or the gram panchayat and insist that they must ensure to get these open drains covered. If the sewage of any particular house makes the neighbourhood dirty we should request them to be more considerate about other’s health.

Q. 8. Describe any three measures for controlling water pollution.

Ans. 8: Water pollution can be controlled—
1. By avoiding release of industrial wastes, household diffuse etc. into river water.
2. By covering the mouths of the wells to ensure that dust leaves etc. may not fall into it.
3. By avoiding washing clothes and bathing with soap near the sources of water.

Q. 9. Fill in the blanks :1. Raw sewage is the _______________ hazard.
2. In _______________ treatment, sewage water is treat with anaerobic bacteria.
3. The solid matter that settles to the bottom of the settling tank is called _______________.
4. The sewage is carried by draingae pipes or _______________.
5. Chlorination is done during _______________ treatment.

Ans. 9:
1. Raw sewage is the health hazard.
2. In secondary treatment, sewage water is treated with anaerobic bacteria.
3. The solid matter that settles to the bottom of the settling tank is called sludge.
4. The sewage is carried by draingae pipes or sewers.
5. Chlorination is done during tertiary treatment.

Q. 10. Describe how sewage is treated.

Ans. 10. Raw sewage is a health hazard. Sewage treatment plants are designed to treat large volume of sewer water and turn it into water that can be considered safe to drink and also put to other uses like agricultural and industrial uses.

In sewage treatment plants, the treatment consists of three stages. In the first stage (called primary treatment), the sewage is passed through coarse screens or sieves. The liquid material is then passed through settling tanks. The suspended materials settle in the tanks and form sludge.

The second stage, called secondary treatment, consists of treating the sewage water that received after first stage with anaerobic bacteria, which break down the sewage water into harmless substances. Moreover, more sludge is formed. At the end of the stage, foul smell of sewage water is not much present.

During the third stage, chlorination is done to kill disease causing organisms. This is also called tertiary treatment.

Q. 11. Fill in the blanks :

1. The suspended matter in the sewage is used to make _________________.
2. Addition of disease causing organisms in water is called water _________________.
3. _________________ bacteria is used to treat sludge.
4. _________________ in open cause health hazards.
5. Sludge and _________________ are the products of water clarification.
6. _________________ is used as manure.

Ans. 11:

1. The suspended matter in the sewage is used to make fertilisers.
2. Addition of disease causing organisms in water is called water contamination.
3. Anaerobic bacteria is used to treat sludge.
4. Defecation in open causes health hazards.
5. Sludge and biogas are the products of water clarification.
6. Activated sludge is used as manure.

Q. 12. Which of the following diseases is caused by polluted water.
(a) typhoid (b) Cholera
(c) hepatitis (d) All of these.

Ans.  12: (d) All of these

Q. 13. Choose true and false statements from the following :

1. Chemicals like chlorine and ozone are used to disinfect water.
2. We should not defecate in open as untreated human excreta is a health hazard.
3. Wastewater cannot be reused.
4. Poor sanitation and contaminated drinking water is the cause of a large number of diseases.
5. Treatment plants increase the pollutants in wastewater.

Ans. 13: 1. T, 2. T, 3. F, 4. T, 5. F.

1. Chemicals like chlorine and ozone are used to disinfect water - True
 
2. We should not defecate in open as untreated human excreta is a health hazard - True

3. Wastewater cannot be reused - False, 

Wastewater can be reused by its treatment at treatment plants.

4. Poor sanitation and contaminated drinking water is the cause of a large number of diseases - True

5. Treatment plants increase the pollutants in wastewater - False (Correct answer is - Treatment plants decrease the pollutants in wastewater).

Q. 14. In sewerage, mainholes are located at every :

(a) 50–60 m (b) 70 – 80 M
(c) 80 – 90 m (d) 90 – 100 m

Ans. 14: (a) 50 – 60 m

(In sewerage, mainholes are located at every 50-60 m).

Q. 15. Which one of the following is a quality of wastewater ?

(a) Dirty and repelling look (b) Bad taste
(c) Fowl smell (d) All the above

Ans. 15: (d) All the above

(Waste water has dirty and repelling look, is bad in taste and has fowl smell, so all the given answers are right).