| A | B | 
|---|
| SEWAGE | Waste material from runoff and domestic sources | 
| CONTAMINANT | Foriegn objects or substances | 
| RUNOFF | Untreated water | 
| TREATED EFFLUENT | Water suitable for use or discharge. | 
| SLUDGE | solid waste material. | 
| PRIMARY TREATMENT | Seperation of solids from waste water. | 
| SECONDARY TREATMENT | conversion of biological  matter by aerobic means. | 
| TERTIARY TREATMENT | Final filtering and cleaning and lagooning | 
| DISINFECTED | Reduction of the number of microorganisms. | 
| AEROBIC | Process done in thepresence of oxygen. | 
| ANAEROBIC | Process done without oxygen. | 
| SAND CATCHER | Sand bed used to collect solid material. | 
| SEDIMENT | Solids that settle out of a solution | 
| FLOCCULENT | Suspended solid particles. | 
| SETTLING TANK | Container that allows suspended particles to settle out. | 
| LAGOON | Man made pond used to aerate water. | 
| EUTRIPHICATION | Excessive buildup of nutrients. |