CPWM Sustainable Waste Management and Resource Recovery 4 — Questions and Answers
Question 1: Under the Basel Convention, 'hazardous waste' shipments between countries require:
- No additional documentation beyond a commercial invoice
- Prior informed consent from the receiving country (Correct answer)
- Only a UN transport manifest
- Approval from the World Trade Organization
Correct answer: Prior informed consent from the receiving country
The Basel Convention mandates prior informed consent (PIC) from the importing country before hazardous waste can be legally shipped across borders.
Question 2: Which waste management strategy is most aligned with the circular economy model?
- Maximizing landfill capacity through compaction
- Designing products for disassembly and material recovery at end of life (Correct answer)
- Increasing incineration capacity to handle mixed waste
- Exporting recyclables to offset domestic sorting costs
Correct answer: Designing products for disassembly and material recovery at end of life
Circular economy principles emphasize designing products so materials can be easily recovered, reused, and reintroduced into production cycles.
Question 3: A recycling program achieves an 80% capture rate for aluminum cans. This means:
- 80% of cans are free of contamination
- 80% of aluminum cans generated are collected for recycling (Correct answer)
- The facility processes 80 tons per hour
- 80% of revenue comes from aluminum sales
Correct answer: 80% of aluminum cans generated are collected for recycling
Capture rate measures the fraction of a targeted material that is actually collected for recycling relative to the total generated.
Question 4: Food waste sent to anaerobic digestion rather than landfill provides which key environmental benefit?
- Eliminates the need for composting infrastructure
- Reduces methane emissions while generating renewable biogas (Correct answer)
- Converts food waste into potable water
- Permanently removes nutrients from the environment
Correct answer: Reduces methane emissions while generating renewable biogas
Anaerobic digestion captures methane as biogas for energy use, preventing its uncontrolled release from landfills and reducing greenhouse gas emissions.
Question 5: When a 'pay-as-you-throw' (PAYT) pricing system is implemented, waste generation typically:
- Increases because residents feel entitled to disposal services
- Decreases as households have a direct financial incentive to reduce waste (Correct answer)
- Stays the same regardless of pricing structure
- Shifts entirely to illegal dumping within weeks
Correct answer: Decreases as households have a direct financial incentive to reduce waste
PAYT programs create a direct economic incentive for households to reduce waste, and studies consistently show measurable reductions in disposed quantities.
Question 6: In construction and demolition (C&D) waste management, 'source separation' refers to:
- Removing hazardous materials before demolition
- Sorting different materials at the job site rather than at a centralized facility (Correct answer)
- Separating recyclables from refuse after transport
- Documenting the origin of each waste load
Correct answer: Sorting different materials at the job site rather than at a centralized facility
Source separation in C&D projects involves sorting materials such as wood, metal, and concrete on-site, which improves recovery rates and reduces contamination.
Question 7: The 'social cost of carbon' concept is relevant to waste management because it helps:
- Set tipping fees for municipal solid waste
- Monetize greenhouse gas reductions from diversion programs (Correct answer)
- Calculate worker compensation at landfills
- Determine the optimal landfill liner depth
Correct answer: Monetize greenhouse gas reductions from diversion programs
The social cost of carbon assigns a dollar value to the climate damage from one ton of CO₂, allowing waste managers to quantify the economic benefit of GHG-reducing diversion strategies.
CPWM Sustainable Waste Management and Resource Recovery 4
Under the Basel Convention, 'hazardous waste' shipments between countries require: