| A | B |
|---|
| groundwater | the underground water supply |
| hazardous wastes | a dangerous chemical bi-product of industry that can poison the water or ground |
| water supply | the water used by a community, such as a reservoir |
| sewage | the used, dirty water that goes down the drain or is flushed by a toilet |
| reservoir | a human-made lake whose water level is often controlled by a dam |
| well | a deep hole dug in order to reach the groundwater |
| sewage treatment plant | a place where used, dirty water is treated chemically or with filters to make it pure again so that it may be returned to the water supply |
| flouride | a salt added to many water supplies to help prevent tooth decay |
| chlorine | a greenish yellow, chemical element used to purify water |
| fresh water | water that has only small amounts of salt |
| pollution | the results of polluting |
| hazardous waste | a dangerous chemical bi-product of industry that can poison the water of ground |
