SWM MCQ Practice Set

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Solid Waste Management MCQ For NEET Biology https://share.google/15q2kZWLYxLB28YoS

Q. How many major sources of solid waste are there based on their origin?

a) 10

b) 5

c) 9

d) 6

Answer: c

Explanation: There are broadly 9 sources of solid waste. They are residential, industrial, commercial, institutional, construction & demolition areas, municipal services, treatment plants, agriculture and biomedical

Q. The important categories of solid waste are:

a) municipal wastes

b) hazardous wastes

c) industrial wastes

d) all of these ✅

Q.Which one of the following solid waste disposal methods is ecologically most acceptable?

A. Sanitary landfill

B. Incineration

C. Composting

D. Pyrolysis

Option 2 : Composting 

Methods for solid waste disposal are:

1. Landfills: In this, Garbage is basically spread out in thin layers, compressed, and covered with soil or plastic foam. It is used in urban areas where a large amount of waste is generated. Leachate is generated in this method that may harm our soil. So A well-designed and laid out leachate collection mechanism is to be provided.

2. Incineration: This method involves the burning of solid wastes at high temperatures until the wastes are turned into ashes It is used when the calorific value of refuse is very high i.e. volume of refuse is reduced significantly.   

3. Composting : is a biological method for the decomposition of organic wastes. This is an environmentally, and economically acceptable method. It can be done either in presence of oxygen or in absence of oxygen. End products formed in this process are called humus or Composed manure. There are mainly two methods (Indore and Bangalore methods) adopted in India for the decomposition of solid wastes by compositing.

4. Shredding: It is the process of size reduction of waste material. 

Q.Sewage sickness occurs when: 

A. sewage contains pathogenic organisms.

B. sewage enters the water supply system

C. sewers get clogged due to accumulation of solids

D. voids of soil clogged due to continuous application of sewage on a piece of land

Answer: Option 4 : Voids of soil clogged due to continuous application of sewage on a piece of land

Explanation: Sewage sickness, When sewage is applied continuously on a piece of land, the soil pores or voids may get filled up and clogged with sewage matter retained in them. Thus the free circulation of air will be prevented and anaerobic conditions will develop within the pores.

This develops anaerobic conditions and foul gasses like methane, carbon dioxide and hydrogen sulphide are evolved.

Prevention , In order to prevent sewage sickness:

(i) Sewage should be given primary treatment

(ii) The soil chosen for effluent irrigation/sewage farming should be sandy or loamy.

(iii) A proper under drainage system (open jointed drains) should be designed.

(iv) Land should be given rest for some time and ploughed thoroughly

(v) Rotation of crops to be followed.

(vi) Shallow depths of water should be applied.

Q1. Which of the following solid wastes describes the term ‘Municipal Solid Waste’?

(a) Toxic

(b) Hazardous

(c) Non-toxic

(d) Non-hazardous

The correct answer is: (d) Non-hazardous

Explanation:

Municipal Solid Waste (MSW) refers to the everyday waste generated from households, offices, shops, schools, and other urban areas. It typically includes food waste, paper, plastics, glass, metals, textiles, and garden waste.

It is generally non-hazardous in nature.

Hazardous and toxic wastes (like industrial chemicals, biomedical waste, radioactive materials) are managed separately under different categories.

👉 So, MSW = non-hazardous waste from urban/municipal sources.

Hazardous and toxic wastes are not included in Municipal Solid Waste (MSW) because:

1. Different Nature of Waste

MSW = mostly non-hazardous, biodegradable, and recyclable waste from households, shops, markets.

Hazardous waste = contains toxic, flammable, corrosive, or infectious materials.

2. Different Treatment & Disposal Methods

MSW is treated by composting, recycling, incineration, or landfilling.

Hazardous/toxic wastes require specialized treatment (incinerators with pollution control, secured landfills, chemical treatment).

3. Health and Environmental Risks

Mixing hazardous waste with MSW can contaminate air, soil, and groundwater.

It also increases risks for sanitation workers and the public.

4. Legal Framework

The Government has made separate rules for different wastes:

Solid Waste Management Rules, 2016 → Municipal Solid Waste.

Hazardous Waste Management Rules, 2016 → Hazardous & toxic wastes.

Biomedical Waste Management Rules, 2016 → Hospital & medical wastes.

E-Waste Rules, 2016 → Electronic wastes.

Radioactive Waste → Atomic Energy Act, 1962.

👉 Summary: Hazardous and toxic wastes are kept separate from MSW because they require special handling, treatment, and disposal due to their dangerous properties.

Q2. Which of the following are related to ‘source reduction’ in integrated solid waste management ?

(A) Reduced Toxicity

(B) Composting

(C) Less Packaging

(D) Landfill

(E) More durable products

Choose the correct answer from the options given below : 

1. (A), (B) and (C) only

2. (A), (C) and (E) only

3. (B), (C) and (D) only

4. (C), (D) and (E) only

Source reduction (also called waste minimization / waste prevention):

It means reducing waste generation at the source itself before it even enters the waste stream.

Examples: Designing less packaging materials

Using more durable products (long life span → less replacement waste)

Reducing toxicity of products so waste generated is less harmful

Now check options:

(A) Reduced Toxicity ✅ (yes, directly source reduction)

(B) Composting ❌ (this is treatment after waste generation, not prevention)

(C) Less Packaging ✅ (classic example of source reduction)

(D) Landfill ❌ (final disposal, not reduction at source)

(E) More durable products ✅ (less frequent disposal → reduction at source)

✅ Correct combination = (A), (C), (E)

Answer: 2. (A), (C) and (E) only 🎯

Q3. The primary source of municipal solid waste is:

A) household waste ✅

B) industrial waste

C) agricultural waste

D) hazardous waste

Explanation: MSW is collected from households, commercial areas, and public spaces through door-to-door collection or community bins. Waste is segregated into biodegradable, recyclable, and non-recyclable components, enabling efficient processing and recycling.

Segregated waste is transported to transfer stations, processing plants, or landfills using covered vehicles. Proper transportation prevents spillage, odor, and environmental contamination during transit.

Biodegradable waste is treated via composting or anaerobic digestion to produce compost or biogas. Recyclable materials like plastics, metals, and glass are sorted and sent to recycling facilities for reuse. Non-recyclable waste may undergo incineration or energy recovery.

Residual waste that cannot be recycled or processed is disposed of in sanitary landfills, designed to prevent leachate and groundwater contamination. Landfills are lined and monitored to minimize environmental and health hazards.

Compost, biogas, and recycled materials are reused for agriculture, energy production, or manufacturing. This reduces landfill burden, conserves natural resources, and promotes a circular economy.

Additional Information

Industrial Waste: Generated from factories and manufacturing units, including chemicals, metals, sludge, and plastics that vary by industry type.

Requires treatment and recycling such as chemical neutralization, filtration, and metal recovery to reduce environmental impact.

Agricultural Waste : Comes from crop residues, animal manure, and husks, rich in organic matter suitable for composting or energy production.

Proper management through composting or biogas production prevents air pollution from burning and enriches soil fertility.

Hazardous Waste: Produced by hospitals, laboratories, chemical industries, and e-waste units, containing toxic, flammable, or biomedical materials.

Needs special handling and treatment like incineration, neutralization, or secure landfilling to protect health and the environment.

Q4. Which of the following best defines solid waste?

A. Gaseous waste from industries

B. Liquid waste from domestic sources

C. Unwanted solid materials from human and animal activities ✅

D. None of the above

Q5 Solid waste can be classified into how many major types?

A.3

B.5

C.6 ✅

D.8

Explanation:  🧾 According to general environmental studies (broad classification):

Solid waste is often divided into 6 major types:

1. Domestic or Residential Waste

2. Industrial Waste

3. Commercial Waste

4. Institutional Waste

5. Construction and Demolition Waste

6. Biomedical (Hospital) Waste

✅ Answer (commonly accepted in exams like UPSC, SSC, State PCS): 6 major types

But if the question is from Environmental Engineering (technical) or Solid Waste Management (as per CPCB), they sometimes group them into 4 broad categories.

1. Municipal Solid Waste (MSW) – household, commercial, and institutional waste.

2. Industrial Waste – produced by manufacturing and industrial processes.

3. Hazardous Waste – toxic, reactive, flammable, or corrosive waste.

4. Biomedical (or Hospital) Waste – waste from healthcare and medical activities.

So —

👉 For UPSC or general studies, prefer 6 types.

👉 For technical or engineering context, 4 types is acceptable.

Q6. Which of the following is an example of hazardous solid waste?

A. Kitchen waste

B. Plastic bottles

C. Batteries ✅

D. Paper waste

Q7. Biomedical waste is generated primarily from:

A. Agriculture

B. Schools

C. Hospitals and clinics ✅

D. Markets

8. Construction and demolition waste includes:

A. Food waste

B. Debris and rubble ✅

C. E-waste

D. Textiles

Q9. E-waste typically contains:

A. Organic waste

B. Bricks and mortar

C. Heavy metals and plastics ✅

D. Agricultural waste

10. The waste generated by shops, restaurants, and offices is known as:

A. Institutional waste

B. Residential waste

C. Commercial waste ✅

D. Industrial waste

Q11. Municipal solid waste (MSW) refers to:

A. Industrial waste only

B. All waste from municipal jurisdiction ✅

C. Only residential waste

D. Agricultural waste

12. Which type of solid waste is generated in the highest volume in urban areas?

A. Agricultural

B. Industrial

C. Residential ✅

D. Biomedical

13. Which one is not considered as municipal solid waste?

A. Paper

8. Metal scraps

C. Fly ash from thermal plants ✅

D. Organic waste

14. Which of the following is a primary source of residential solid waste?

A. Clinics

B. Factories

C. Households ✅

D. Hotels

15. Which sector contributes to hazardous and chemical sludge waste?

A. Educational

B. Commercial

C. Industrial ✅

D. Residential

16. Institutional solid waste includes waste from:

A. Markets

B. Hospitals and schools ✅

C. Homes

D. Construction sites

17. The largest source of organic solid waste is:

A. Construction sites

B. Industries

C. Agriculture ✅

D. Educational institutions

18. Street sweepings are a part of which waste category?

A. Domestic waste

B. Municipal services waste ✅

C. Institutional waste

D. Agricultural waste

19. The process of burning of municipal solid waste at high temperature is called ____________

a) Incineration

b) Composting

c) Land filing

d) Shredding

Answer: a

Explanation: Incineration is the most sanitary method of disposal of municipal solid waste. Solid waste should have a high calorific value.

20. Which of the following is a biodegradable waste?

a) Polythene bags

b) Synthetic fiber

c) Food waste

d) Paper

Answer: c

Explanation: Polythene bags, synthetic fiber and paper are non biodegradable wastes whereas food waste is a biodegradable waste.

21. In which method of disposal of municipal solid waste, the waste is dumped in the soil?

a) Incineration

b) Composting

c) Land filing

d) Shredding

Answer: c

Explanation: Land filling is a process of disposal of solid waste under the soil. It is usually done in low lying areas to prevent unhygienic conditions.

22. Which of the following is not correct regarding disposal of waste by land filling?

a) Economical method

b) Preferred in low lying areas

c) Foul gases are not produced

d) Separation of different types of waste required

Answer: c

Explanation: Land fill gases are produced during the dumping of waste. They are foul smell creating unhygienic conditions.

23. The density of ash produced in the municipal solid waste is ___________

a) 100 kg/m3

b) 450 kg/m3

c) 700 kg/m3

d) 1000 kg/m3

Answer: c

Explanation: The range of the density of ash produced from the municipal solid waste is 700-850kg/m3.

24. The process of decomposition of biodegradable solid waste by earthworms is called ___________

a) Land fills

b) Shredding

c) Vermi-composting

d) Composting

Answer: c

Explanation: The process of decomposition of biodegradable solid waste by earthworms is called Vermi-composting.

25. The waste produced in cotton mills are ___________

a) Municipal solid waste

b) Non biodegradable waste

c) Hazardous waste

d) Non hazardous waste

Answer: d

Explanation: The industrial waste is produced by cotton mills which are biodegradable and are non hazardous.

26. Which of the following is not the land filling method?

a) Bangalore method

b) Area method

c) Depression method

d) Trench method

Answer: a

Explanation: Bangalore method is a method of composting whereas area, depression and trench method are the land filling method.

27. ______ is a liquid that passes through solid waste and extracts suspended impurities from it.

a) Leachate

b) Sludge

c) Distilled water

d) Municipal waste

Answer: a

Explanation: Leachate is a liquid that passes through solid waste and extracts suspended impurities from it. It can be minimized by the use of clay lines.

28. Which of the following is not the municipal solid waste?

a) Radioactive substance

b) Ashes

c) Food waste

d) Rubbish

Answer: a

Explanation: Rubbish, food waste and food waste are municipal solid waste, whereas radioactive substances are industrial waste.

29. Which of the following waste can be decomposed by bacteria?

a) Radioactive substance

b) Ashes

c) Food waste

d) Rubbish

Answer: c

Explanation: Food waste can be decomposed by bacteria as they are biodegradable waste, whereas ashes, rubbish is non biodegradable.

30. ______ is the cutting and tearing of municipal solid waste.

a) Land fills

b) Shredding

c) Pulverization

d) Composting

Answer: b

Explanation: Shredding is the cutting and tearing of municipal solid waste. It helps in reducing the size and volume of municipal solid waste.

31. _________ is the crushing and grinding of municipal solid waste.

a) Land fills

b) Shredding

c) Pulverization

d) Composting

Answer: c

Explanation: Pulverization is the crushing and grinding of municipal solid waste. It changes the character of municipal solid waste and reduced its volume by 40%.

32. In which method of composting, decomposition of anaerobic waste takes place?

a) Indian method

b) Depression method

c) Bangalore method

d) Trench method

Answer: c

Explanation: In the Bangalore method of composting, decomposition of anaerobic waste takes place. It is better than the Indore method.

33. Which of the following is a biological method of disposal of municipal solid waste?

a) Land fills

b) Shredding

c) Pulverization

d) Composting

Answer: d

Explanation: Composting is a biological method of decomposing the municipal solid waste under aerobic and anaerobic condition. It results in the production of humus.

34. Which of the Following Ones Is the Simplest and Most Common Method Used in the Cities to Dump the Wastes That Are Collected?

a) River

b) Ocean

c) Landfill

d) None of the above

Answer: (c)

Explanation: The most widely utilized form of trash disposal today is to dump everyday waste/garbage in landfills. This garbage disposal method relies on burying the material in the ground. In developing countries, landfills are common.

35. Which of the Following Methods is a Good One in Dealing With the Solid Waste Problem?

A. Landfilling

B. Recycling

C. Both a and b

D. None of the above

Answer: (b)

Explanation: Solid waste recycling is the greatest solution. It is the process of transforming garbage into a new or usable product in order to avoid waste disposal. Obviously, the landfill method of disposal has numerous drawbacks.

36. How Many Main/Primary Components Exist in Integrated Waste Management?

A. Two

B. Three

C. Seven

D. Eleven

Answer: (B)

Explanation: Source reduction, recycling, and disposal are the three key components of an integrated waste management strategy. These three categories of garbage all play a critical role in solid waste management.

Q37. Which component of MSW has the highest calorific value?

MSW के किस घटक का ऊष्मीय मूल्य सबसे अधिक होता है?

A) Food waste / खाद्य अपशिष्ट

B) Plastics and rubber / प्लास्टिक और रबर

C) Yard waste / बागवानी अपशिष्ट

D) Paper / कागज

Answer / उत्तर: B) Plastics and rubber

Explanation / व्याख्या: Plastics and rubber are carbon-rich materials and have higher energy content compared to wet organics.

Q38. Which factor primarily affects the biodegradability of MSW?

MSW के जैविक क्षय पर मुख्य रूप से कौन सा कारक प्रभाव डालता है?

A) Moisture content / नमी की मात्रा

B) Ash content / राख की मात्रा

C) Metal content / धातु की मात्रा

D) Glass content / कांच की मात्रा

Answer / उत्तर: A) Moisture content

Explanation / व्याख्या: High moisture and organic content increase biodegradation rates.

Q39. The bulk density of MSW is important for:

MSW का बल्क डेंसिटी किसके लिए महत्वपूर्ण है?

A) Collection and transportation / संग्रह और परिवहन

B) Incineration temperature / दहन तापमान

C) Compost nutrient content / कम्पोस्ट पोषक तत्व सामग्री

D) Pathogen removal / रोगजनक निष्कासन

Answer / उत्तर: A) Collection and transportation

Explanation / व्याख्या: Bulk density determines vehicle load capacity and storage volume.

Q40. Ideal C/N ratio for composting MSW is:

MSW को कम्पोस्ट करने के लिए आदर्श C/N अनुपात है:

A) 10–15 / 10–15

B) 25–30 / 25–30

C) 40–50 / 40–50

D) 5–10 / 5–10

Answer / उत्तर: B) 25–30

Explanation / व्याख्या: The ideal carbon-to-nitrogen ratio promotes microbial activity for efficient composting.

Q41. Seasonal variation in MSW composition is mainly due to:

MSW के संघटन में मौसमी बदलाव मुख्य रूप से किस कारण से होता है?

A) Population density / जनसंख्या घनत्व

B) Cultural and lifestyle patterns / सांस्कृतिक और जीवनशैली पैटर्न

C) Incineration facilities / दहन सुविधाएँ

D) Bulk density / बल्क डेंसिटी

Answer / उत्तर: B) Cultural and lifestyle patterns

Explanation / व्याख्या: Festivals, harvest, and diet habits change the proportion of organics, paper, and other wastes.

Q42. High moisture in MSW affects:

MSW में उच्च नमी किसे प्रभावित करती है?

A) Energy content / ऊर्जा सामग्री

B) Biodegradability and leachate generation / जैविक क्षय और लीचेट उत्पादन

C) Metal recovery / धातु पुनर्प्राप्ति

D) Glass recycling / कांच पुनर्चक्रण

Answer / उत्तर: B) Biodegradability and leachate generation

Explanation / व्याख्या: Moist organic waste decomposes faster and produces more leachate.

Q43. Pathogens in MSW are mostly associated with:

MSW में रोगजनक मुख्य रूप से किससे जुड़े होते हैं?

A) Plastic / प्लास्टिक

B) Organic waste / जैविक अपशिष्ट

C) Metals / धातु

D) Glass / कांच

Answer / उत्तर: B) Organic waste

Explanation / व्याख्या: Food and biodegradable waste harbor bacteria, viruses, and parasites.

Q44. Proximate analysis of MSW does NOT include:

MSW का प्रॉक्सिमेट विश्लेषण निम्नलिखित में से किसे शामिल नहीं करता?

A) Moisture / नमी

B) Volatile matter / अस्थायी पदार्थ

C) Heavy metals / भारी धातुएँ

D) Ash content / राख की मात्रा

Answer / उत्तर: C) Heavy metals

Explanation / व्याख्या: Proximate analysis measures moisture, volatile matter, fixed carbon, and ash, not metals.

What plan should we make to the disposal of solid waste?

a) Integrated waste management plan

b) Recycling of waste management plan

c) Reducing of waste management plan

d) Use of waste management plan

Answer: a

Explanation: The disposal of solid waste should be part of an integrated waste management plan. This integrated solid waste management is the method of collection, processing, resource recovery and final disposal of solid waste.

How many key characteristics of a municipal sanitary landfill are there?

a) One

b) Two

c) Three

d) Four

Answer: c

Explanation: The three key characteristics of a municipal sanitary landfill that distinguish it from an open dump are: Solid waste is placed in a suitably selected and prepared landfill site, the waste material is spread out and compacted with appropriate heavy machinery, the waste is covered each day with a layer of compacted soil.

Which of the following is both inorganic and organic?

a) Sewage Sludge

b) Liquid crystalline

c) Natural gas

d) Semicrystalline

Answer: a

Explanation: Sewage Sludge is produced during primary and secondary treatment phases and are usually sticky and has pathogens, so, it is both inorganic and organic, whereas, Liquid crystalline and Semi crystalline are optically active polymer that can activate in response to heat, light, electrical field etc. and hence, is not is inorganic or organic and natural gas is usually a hydrocarbon which is non-renewable.

Which of the following is a visual pollution?

a) Insightfulness of piles of garbage

b) Mashing with Adhesives

c) Mashing with Fibers

d) Flowers

Answer: a

Explanation: Insightfulness of piles of garbage which offends the aesthetic feeling is referred to as visual pollution, whereas, mashing with Adhesives or fibers is not related to visual pollution and flowers are fine-looking to watch.

36. Which of the following methods cannot be used for waste disposal?

Dumping

b) Gasification

c) Incineration

d) Open sea disposal

Answer: d

Explanation: If open sea disposal method is used for disposing waste, a lot of aquatic organisms would be affected and in long run it might affect other land organisms as well, whereas, dumping is done in low lying areas, gasification is the degradation of organic matter in anaerobic conditions and incineration involves chemical reaction, all these methods doesn’t cause much damage to the environment.

Which of the following is an important part of the natural release of biogas in the environment?

a) Biogeochemcial cycle

b) Environment pollution

c) Afforestation

d) Deforestation

Answer: a

Explanation: The natural release of biogas in the environment due to the activity of methanogens leads is crucial for biogeochemical cycle, whereas, biogas does not lead to a considerable amount of environment pollution, afforestation and deforestation are caused by human intervention.

Which of the following organism degrade the organic matter thereby, transfer the matter to the environment?

a) Methanogens

b) Manganese

c) Carbon dioxide

d) Methane

Answer: a

Explanation: Methanogens degrade the organic matter under anaerobic conditions producing natural biogas, whereas, manganese, carbon dioxide and methane are not microorganisms that degrade the organic matter.

Which of the following temperature is optimum for incinerators?

a) 900-1100°C

b) 100-110°C

c) 90-110°C

d) 100-11000°C

Answer: a

Explanation: 900-1100°C is the optimum temperature for incinerators which operates in the combustion zone which results in good combustion and also protects the inside walls of the incinerator. Temperature above and lower this range wouldn’t result in good combustion and might harm the incinerator as well.

Which of the following resembles the rich topsoil in context to solid waste composting?

a) Humus

b) Bed rock

c) Sub soil

d) Weathered rock

Answer: a

Explanation: The dark substance in the top layer of the soil which looks like peat and has a powdery texture is humus, sub soil, weathered rock bed rock are the subsequent layers after the top layer.

Why mismanagement of battery waste can be harmful?

a) Texture

b) Heavy metals

c) Plastics

d) Odor

Answer: b

Explanation: Battery recycling is very vital as it contains heavy metals like cadmium, lead and mercury which if comes in contact with the environment is very harmful. Hence, should be handled properly. Odor and texture is not hazardous; plastics is a major concern but is not related to the batteries waste.

Why recycling of metal is more cost-effective?

a) Extraction of metal increases

b) Increases operating cost

c) Reduces operating cost

d) Reduces odor

Answer: c

Explanation: Recycling of metal highly reduces the operating cost and the industrial cost as extraction cost is reduced and energy consumption is also reduced, extraction of metal decreases and odor is not relative.

Which of the following is not a Biomedical waste?

a) Animal waste

b) Microbiological waste

c) Chemical waste

d) Domestic waste

Answer: d

Explanation: Domestic waste doesn’t contain any infectious agents and is totally degradable in nature but animal waste contains animal tissue and organs, microbiological waste contains microbiological specimen wastes, chemical waste contains disinfectant chemicals. So, all of these wastes are treated as Biomedical wastes.

Which of the following is categorized as an incineration waste?

a) Incineration ash

b) Animal waste

c) Solid waste

d) Cytotoxic drugs

Answer: a

Explanation: Incineration ash comes from any biomedical wastes that is being incinerated and ignited and burnt to dispose of the biomedical wastes. This prevents further contamination but this also creates Incineration ash, which has the potential of causing a disease and hence, it’s treatment is very necessary for the public health, whereas, animal waste contains animal tissue and organs, Solid waste can be any wastes from the hospitals or labs like cotton, blood tubing, catheters etc. and cytotoxic drugs are used and old expired medicines.

Which of the following should not be mixed with other wastes to avoid contamination?

a) Tarry residue

b) Oily sludge

c) Animal waste

d) Vegetable oil

Answer: c

Explanation: Animal waste is a type of biomedical waste that contains animal tissue and organs and it is not safe for contamination with other wastes as they are infectious. Tarry residue, oily sludge, are hazardous waste of petrochemical processes which should be handled correctly and disposed of carefully without causing any damage to the environment, but it certainly is not infectious. Vegetable oil doesn’t pose any threat as it’s a kitchen waste and domestic wastes are biodegradable.

Which of the following is not a waste treatment method for biomedical wastes?

a) Incineration

b) Chemical disinfecting

c) Autoclaving

d) Sieving

Answer: d

Explanation: Sieving is a physical method of separation of bigger molecules and it cannot be used in a waste treatment method, whereas, incineration, chemical disinfecting, autoclaving, encapsulation are the methods used for waste treatment of biomedical wastes.

Which of the following requires special treatment of bacteria?

a) Packaging of waste

b) Labelling of waste

c) Transport of waste

d) Degradation of waste

Answer: d

Explanation: Degradation of waste especially biomedical wastes requires some special treatment of bacteria or other microorganisms, whereas, Packaging, labelling and transport of biomedical wastes should be done properly in order to avoid any hazardous contamination of the wastes with the environment and with humans that can be infectious.

The method of refuse disposal, involving burial in trenches, is called

A. incineration

B. pulverisation

C. composting

D. none of these

Answer- D

Which of the following materials are used as landfill sealants for the control of gas and leachate movements?

1. Lime

2. Sand

3. Bentonite

4. Fly ash

5. Butyl rubber

Select the correct answer using the codes given below:

A. 1, 2 and 3

B. 4 and 5

C. 3 and 5

D. 1, 2 and 4

The correct option is C. 3 and 5.

Explanation: 

Bentonite: Bentonite, specifically sodium bentonite, has a very low permeability and is used in geosynthetic clay liners (GCLs) to create an effective barrier against leachate and gas movement.

Butyl rubber: This material is a type of synthetic rubber that can be used as a flexible membrane liner in landfills. It provides an impermeable barrier to prevent leachate from seeping into the surrounding soil and groundwater. 

1. Lime, 2. Sand, and 4. Fly ash: While these materials may be used in other aspects of landfill construction or stabilization, they are not primarily used as sealants to control the movement of gas and leachate. Sand, for example, is often used in drainage layers to collect and transport leachate, which is the opposite function of a sealant.