Sewage and refuse disposal - JSS1 Physical and Health Education Past Questions and Answers - page 2

The purpose of a sewage treatment plant is to clean wastewater before releasing it back into the environment. The treatment process typically involves primary treatment to remove large particles and solids, secondary treatment using bacteria to break down organic matter, and tertiary treatment to remove any remaining contaminants.

Composting benefits the environment by turning organic waste, such as food scraps and yard waste, into nutrient-rich soil. This process reduces the amount of waste sent to landfills, decreases methane emissions, and provides a natural fertilizer that enhances soil quality and supports plant growth.

Common sources of water supply for human use include surface water from rivers, lakes, and reservoirs; groundwater from underground aquifers accessed through wells; rainwater collected and stored through rainwater harvesting systems; and desalinated water obtained by removing salt from seawater.

Clean water is essential for human health because it is necessary for drinking, which helps in digestion, nutrient absorption, and maintaining body temperature. It also plays a crucial role in sanitation and hygiene practices, such as washing hands, bathing, and cleaning, which help prevent diseases and maintain overall health.