Green Gold Cassava Plant: Choosing Between Three Sites
Green Gold Ltd wants to build a cassava processing plant turning 60 tonnes of fresh roots a day into flour and starch. Fresh roots lose quality within 48 hours and are heavy, so haulage is costly. Three sites are available. Site A is 4 km from the main cassava district (900 smallholders), 22 km from the capital's port, with unreliable three-phase power and a seasonal water supply; land costs $180,000 per hectare. Site B is beside the port, 60 km from the farms, with reliable power, a water main and land at $650,000 per hectare. Site C is on the edge of a market town of 25,000, 35 km from the farms, with a paved road and a labour pool of 4,000, but strong local opposition over odour and truck traffic; land costs $240,000 per hectare. The company needs 2 hectares, 85 workers and a guaranteed 400 m³ of water a day. It expects to export 60% of output and sell 40% locally. A five-year tax holiday applies only to projects outside the capital region.
1. Recommend a site using weighted criteria. Show how you weigh the factors rather than simply choosing the cheapest land.
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Set weights before scoring, because the plant's product is perishable, water-hungry and export-oriented.
| Factor | Weight | A | B | C |
|---|---|---|---|---|
| Water security | 25% | 1 | 5 | 3 |
| Power reliability | 20% | 1 | 5 | 3 |
| Haulage/perishability | 20% | 5 | 1 | 4 |
| Market and port access | 15% | 4 | 5 | 4 |
| Labour | 10% | 2 | 3 | 5 |
| Planning/community risk | 10% | 4 | 4 | 1 |
Weighted scores: A ≈ 2.55, B ≈ 3.85, C ≈ 3.35.
But raw scores hide three decisive points. Site A is disqualified in practice: unreliable power and seasonal water would halt a continuous process and spoil food product, and a generator plus a borehole adds cost that the cheap land ($360,000 total) cannot offset. Site B is technically strong but 60 km of haulage on a root that degrades within 48 hours risks rejections, and it is inside the capital region, so it loses the five-year tax holiday. Site C balances a manageable 35 km haul, a local market for the 40% domestic sales, labour and transport - its weakness is consent, not geography.
Recommendation: Site C, conditional on effluent and odour controls and a traffic management agreement. Missing data on power and water at C must be checked first.
2. Explain why the least-cost site on paper is often not the site a real firm chooses.
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Land and transport are only two lines in a much longer cost and risk calculation.
- Hidden capital costs: Site A's land is cheapest ($360,000 for 2 ha against $1.3m at B), but unreliable power means a standby generator, fuel storage and voltage stabilisers; a seasonal water supply means a storage tank or borehole. Those costs may exceed the land saving within a few years.
- Operating losses, not just costs: roots spoil within 48 hours. A 60 km haul from B through traffic adds delay, and a rejected load is a total loss of 60 tonnes, not a small transport premium. Firms avoid unpredictable losses more than they chase cheap land.
- Revenue access: the export market needs the port, the local market needs buyers. A site with poor access loses sales, which does not appear in a land-price comparison.
- Incentives: the tax holiday is available only outside the capital region, so Site B carries a five-year penalty that a simple cost table misses.
- Risk and consent: Site C's opposition could mean a public inquiry, delay, or operating conditions costing more than the land differential. Firms price in delay.
- Labour and skills: a pool of 4,000 at C reduces recruitment and training costs; 85 workers are not easily found in a rural parish.
Site selection is therefore a judgement about total cost, reliability and permission, not a search for the cheapest hectare.
3. Discuss one social or environmental issue the chosen site creates and how it could be managed.
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Issue: effluent and odour from processing 60 tonnes of roots a day.
Cassava processing produces peel, wash water and starch-rich effluent with a very high oxygen demand. If discharged untreated, it strips oxygen from a stream, kills fish and creates smell - precisely the objections raised at Site C. The plant also generates lorry traffic: 60 tonnes inbound plus waste outbound means several heavy vehicles an hour on a road through a town of 25,000, with dust, noise and danger near schools.
Management:
- Build a settlement lagoon or anaerobic digester and reuse the biogas for heat; test discharge against national standards before commissioning.
- Compost or pellet the peel rather than dumping it, and sell it as stock feed or fertiliser.
- Site the intake and loading bays away from the residential edge, with a bunded yard and covered conveyors to control dust and odour.
- Agree fixed delivery hours with the town council, and contribute to a road junction or bypass improvement.
- Publish monitoring results so the community can verify compliance.
Without these, the 85 jobs and local market benefits may be outweighed by nuisance - and a plant that loses its social licence may face protests, licence delays or closure.