Waste Management — I Impact of Waste Accumulation — Question 18
Back to all questionsMethane gas is gas produced by the decomposition of accumulated waste.
This gas is highly inflammable, and can cause an explosion if not managed properly.
Key Concepts Covered
This question tests your understanding of the following concepts from the chapter Waste Management — I Impact of Waste Accumulation: Question, Gas, Produced, Decomposition, Accumulated, Waste. These are fundamental topics in Geography that students are expected to master as part of the ICSE Class 10 curriculum.
A thorough understanding of these concepts will help you answer similar questions confidently in your ICSE examinations. These topics are frequently tested in both objective and subjective sections of Geography papers. We recommend revising the relevant section of your textbook alongside practising these solved examples to build a strong foundation.
How to Approach This Question
Read the question carefully and identify what is being asked. Break down complex questions into smaller parts. Use the terminology and concepts discussed in this chapter. Structure your answer logically — begin with a definition or key statement, then provide supporting details. Review your answer to ensure it addresses all parts of the question completely.
Key Points to Remember
- Reference specific locations, latitudes, or regions in your answers.
- Explain both physical and human factors where applicable.
- Use map references and diagrams to strengthen answers.
- Link geographic concepts to current real-world examples.
Practice more questions from Waste Management — I Impact of Waste Accumulation — Geography, Class 10 ICSE
Chapter Overview: Waste Management
Waste Management is the collection, transport, processing, recycling, and disposal of waste materials. This chapter covers the classification of waste into biodegradable and non-biodegradable categories, solid waste management methods (composting, incineration, sanitary landfills), the three stages of sewage treatment (primary, secondary, tertiary), and the management of special waste categories including biomedical waste, electronic waste (e-waste), and nuclear waste. The 3Rs principle (Reduce, Reuse, Recycle) forms the foundation of sustainable waste management. India generates over 62 million tonnes of municipal solid waste annually, of which only about 20% is processed. The Swachh Bharat Abhiyan launched in 2014 aims to improve waste management across the country. Students must understand the differences between waste disposal methods, their advantages and limitations, and be able to suggest appropriate management strategies for different types of waste. The waste-to-energy concept, where non-recyclable waste is converted into electricity or fuel, is an emerging area of focus.
Key Definitions & Concepts
| Term | Definition |
|---|---|
| Biodegradable Waste | Waste that can be decomposed by microorganisms into simpler, non-toxic substances (e.g., food scraps, paper, dead leaves, animal dung) |
| Non-biodegradable Waste | Waste that cannot be broken down by natural biological processes; persists for hundreds of years (e.g., plastic, glass, metals, Styrofoam) |
| Composting | Aerobic decomposition of organic waste by microorganisms to produce humus (nutrient-rich fertiliser) |
| Vermicomposting | Composting using earthworms (Eisenia fetida) to accelerate the decomposition of organic matter |
| Incineration | Controlled burning of waste at 800–1000°C in specially designed furnaces; reduces volume by up to 90% |
| Sanitary Landfill | Engineered waste disposal site with impermeable liner, leachate collection system, daily soil cover, and gas venting |
| Leachate | Contaminated liquid that drains from a landfill, containing dissolved organic and inorganic pollutants |
| BOD | Biochemical Oxygen Demand – the amount of dissolved oxygen needed by aerobic organisms to decompose organic matter in water; higher BOD indicates greater pollution |
| E-waste | Discarded electronic devices containing hazardous materials (lead, mercury, cadmium) that require specialised recycling |
| 3Rs | Reduce (minimise waste), Reuse (use items again), Recycle (reprocess into new products) – the hierarchy of sustainable waste management |
| Waste-to-Energy | Conversion of non-recyclable waste into electricity, heat, or fuel through incineration with energy recovery, gasification, or pyrolysis |
Must-Know Concepts
- Biodegradable waste decomposes naturally (days to months); non-biodegradable waste persists for centuries
- 3Rs hierarchy: Reduce > Reuse > Recycle (prevention is better than treatment)
- Composting is suitable only for organic/biodegradable waste; produces humus used as fertiliser
- Incineration reduces volume by 90% and is essential for biomedical and hazardous waste
- Sanitary landfill key features: impermeable liner + leachate collection + daily soil cover + gas venting
- Sewage treatment has three stages: Primary (physical) → Secondary (biological) → Tertiary (chemical)
- Secondary treatment reduces BOD by 85–90% using aerobic bacteria in aeration tanks
- Biomedical waste uses colour-coded bins: Yellow, Red, Blue, White (puncture-proof for sharps)
- E-waste contains heavy metals (lead, mercury, cadmium); managed through EPR and authorised recyclers
- Nuclear waste management: vitrification (converting to glass), deep geological repositories, lead-lined containers
- India generates 62 million tonnes of MSW annually; is the 3rd largest e-waste producer globally
Biodegradable vs Non-biodegradable Waste
| Feature | Biodegradable Waste | Non-biodegradable Waste |
|---|---|---|
| Decomposition | Broken down by microorganisms | Cannot be decomposed naturally |
| Time | Days to months | Hundreds to thousands of years |
| Examples | Vegetable peels, paper, cow dung | Plastic, glass, aluminium cans |
| Management | Composting, vermicomposting, biogas | Recycling, incineration, sanitary landfill |
Sewage Treatment Stages
| Stage | Type | Process | What is Removed |
|---|---|---|---|
| Primary | Physical | Screening, grit removal, sedimentation | Large debris, sand, suspended solids |
| Secondary | Biological | Aeration with activated sludge (bacteria) | Dissolved organic matter (BOD reduced 85–90%) |
| Tertiary | Chemical | Chlorination, UV treatment, filtration | Pathogens, nutrients (N, P), colour, odour |
Important Diagrams to Practice
- Flow chart of sewage treatment (Primary → Secondary → Tertiary)
- Cross-section of a sanitary landfill showing liner, waste layers, soil cover, leachate collection, gas venting
- Waste management hierarchy pyramid (Prevention > Reuse > Recycling > Recovery > Disposal)
- Colour-coded biomedical waste bins with waste categories
Common Mistakes
- Confusing biodegradable with recyclable (paper is both; glass is recyclable but not biodegradable)
- Swapping secondary (biological) and tertiary (chemical) stages of sewage treatment
- Forgetting to mention the impermeable liner as the key feature of a sanitary landfill
- Calling open burning “incineration” (incineration is controlled burning in a furnace with emission controls)
- Not providing specific Indian examples when asked (Okhla WtE plant, E-Waste Rules 2016, Swachh Bharat)
Board Exam Tips
- Use comparison tables for 5-mark answers (biodegradable vs non-biodegradable, composting vs incineration vs landfill)
- Always define the term first, then explain with examples
- For sewage treatment, draw a flow diagram if asked for explanation
- Mention the 3Rs in order: Reduce → Reuse → Recycle with one example each
- Know the colour-coded bins for biomedical waste (Yellow, Red, Blue, White)