Sewage Treatment

What is one of the pollutants that might be present in waste water from homes?

• Carbon dioxide

• Oxygen

• Harmful bacteria and high levels of nitrogen compounds

• Sand

What type of waste water may contain toxic metal compounds?

• Rainwater

• Industrial

• Residential

• Agricultural

What is the purpose of sedimentation in sewage treatment?

• To add more water

• To allow tiny particles to settle out from still water

• To introduce more bacteria

• To increase the temperature of the sewage

What happens to the sewage sludge during treatment?

• It is released into the environment

• It is recycled

• It is burned

• It is digested anaerobically by specific bacteria

What is used to treat the effluent in the final step of sewage treatment?

• Ozone

• Chlorine

• Ultraviolet light

• Aerobic bacteria