Across
- 2. Related to uninfected ,cleaniness ,hygiene
- 5. Solid waste removed during sewage treatment
- 6. A substance which something impure
- 7. Micro organisms which can cause many diseases
Down
- 1. Used or contaminated water
- 2. A network of pipes carrying sewage
- 3. Liquid waste products released in sewers
- 4. Environment friendly gas produced using organic matter