Across
- 2. Water safe to drink
- 3. when solid matter settles to the bottom of the tank
- 5. Human waste is known as _________ matter
- 7. another process for removing salt from water
- 8. process used to remove solid waste
- 9. Use of sludge
- 10. the type of respiration used to digest sludge
Down
- 1. process of removing salt from water
- 4. used a disinfectant to kill microbes
- 6. Aerobic ________ is used to break down harmful chemical substances