Water

3. conditions relating to public health, especially the provision of clean drinking water and adequate sewage disposal.
6. thick, soft, wet mud or a similar viscous mixture of liquid and solid components, especially the product of an industrial or refining process.
7. the introduction of air into a material.
8. the provision of drainage by sewers.
9. an underground conduit for carrying off drainage water and waste matter.

1. a polluting or poisonous substance that makes something impure.
2. bacteria that can grow and live when oxygen is present.
4. water that has been used in the home, in a business, or as part of an industrial process.
5. gaseous fuel, especially methane, produced by the fermentation of organic matter.
6. waste water and excrement conveyed in sewers