A Zero-Waste Proposal and 1,900 Tonnes of Plastic
A third-year class in a coastal city in Fukui Prefecture is preparing a proposal for the city's "zero-waste" policy. The city produces about 8,400 tonnes of household and business waste a year, of which about 1,900 tonnes is plastic. Roughly 1,100 tonnes of that plastic is containers and packaging, and the rest is products such as toys, buckets and pens. Until recently the city sold about 600 tonnes of mixed plastic a year to exporters. New international rules on plastic waste shipments, in force since 2021, restrict shipments of mixed and contaminated plastic unless the importing country agrees and the waste is sorted to a clean standard. The city's sorting guide accepts only washed containers. A citizens' group proposes three options: (A) keep exporting but require residents to wash and separate everything; (B) build a small incinerator with heat recovery; (C) ban single-use plastic sales in city facilities and expand repair and reuse. The class must recommend one and justify it.
1. Using the figures, estimate how much plastic option A could realistically handle. What limits does the arithmetic reveal?
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Option A can only reach the container portion, so it cannot cover the problem.
- Total plastic: 1,900 t. Containers and packaging: 1,100 t. Other plastic products: about 800 t.
- The 600 t previously exported was mixed plastic; under the stricter rules, contaminated or mixed loads can no longer simply be shipped, so that route shrinks rather than expands unless sorting improves.
- If every resident washed and separated perfectly, at best about 1,100 t of clean containers could be sent for recycling - more than 600 t, so sorting does help the container stream.
- But about 800 t of toys, buckets and pens are not containers, so washing cannot make them acceptable under the city's own guide, and they still need a destination.
The class should state this assumption openly: the gain depends on compliance being near-perfect, which no city achieves, and the 800 t is untouched either way.
2. Which option should the class recommend? Justify your choice by comparing the three against the city's goal and the data.
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Recommend C as the main proposal, with improved sorting (A) as a supporting measure.
- B, incineration: heat recovery is real, but a small plant for a city of this size carries high cost per tonne, and it needs a guaranteed supply of waste for decades. That works against reducing waste, and plastic is fossil carbon, so burning it adds CO2.
- A, export-led sorting: it improves the 1,100 t container stream but leaves the 800 t of other plastic with no route, and it moves the disposal burden to the importing country, which contradicts a "zero-waste" claim.
- C: it is the only option that reduces the 1,900 t rather than relocating it, and it targets single-use items that become waste immediately.
The weakness of C is that the class has no figure for how much plastic city facilities use, so the recommendation should include a one-year measurement before a full ban.
3. A resident says, "Burning plastic is fine because the heat is used to generate electricity." How should the class respond?
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The class should accept the energy point but challenge the conclusion.
Heat recovery does capture some value, and in Japan a large share of plastic "recycling" is in fact thermal recovery, so the resident is describing something real. But three things follow. First, plastic is made from fossil fuels, so burning it releases CO2 that recycling or reuse would largely avoid. Second, an incinerator needs constant feedstock; once built, the city has an interest in producing enough waste to run it, which competes with reduction. Third, burning leaves ash that must go to landfill, so the waste does not disappear.
The right framing is a comparison: CO2 and cost per tonne avoided, and landfill space used, for incineration versus reduction and reuse. Without those numbers the resident's claim is a plausible opinion, not a demonstrated advantage; the class should present it as an open question with the data it still needs.