SAQs
Now that you have completed this study session, you can assess how well you have achieved its Learning Outcomes by answering these questions.
Which of the following waste disposal methods would you consider to be the safest to public and environmental health? Explain the reasons for your choice and why the other two options are less desirable.
- Disposal into open field away from residential areas.
- Disposal into a river.
- Disposal in a sanitary landfill.
Option (3), sanitary landfill, is the safest option.
If a community wanted to transform its open dump site into a controlled landfill, what measures would it have to take?
Measures to transform an open dump site into a controlled landfill should include:
- surrounding the site with a child-proof and animal-proof fence
- employing a person to staff the site
- providing a tractor to spread and compact the waste
- covering the freshly deposited waste with a layer of soil each day.
Explain how incineration differs from open burning.
Incineration is burning that is enclosed and controlled. Open burning is uncontrolled. Incineration produces less smoke; the ash is contained and can be removed for burial; it is safer because the burning waste cannot be blown around and spread fire. A higher temperature can be maintained in an incinerator which ensures more of the waste is consumed, leaving little residue.
What are the key factors to be considered when planning a new landfill in small and medium-sized towns? List at least four factors.
Key factors to consider when planning a landfill in small and medium-sized towns include:
- available land
- required land area based on population size, both current and future, and estimated waste production rate
- distance from the site to the town to be served
- location of rivers that could be polluted
- presence of groundwater below the site
- soil type and geology
- local opinions and beliefs about the site.