water pollution

3. an area with very low oxygen and very little marine life still alive
4. apart of the septic system and receives the wastewater from the houses
8. bacteria that live in the intestines of humans and animals and can pollute water with E.coli
9. acid despoisted as rain and snow and gases that attach to plants and soil
11. not dangerous at small levels but can contaminate water and human activity increases it in groundwater
12. naturally occurring heavy metal found in water due to human activity
14. increase in nutrients in a body of water due to runoff which causes lots of animal death
17. that shows whether or not disease causing animals are present
18. compounds used to manufacture plastics and cause many environment problems
19. solid waste from wastewater
21. fairly clear water in the middle of a septic tank
22. change in temperature of water that kills organisms
23. pond filled with manure produced by livestock

1. control pest organisms that are a threat to crops and human health
2. legislation that keeps the water clean and protects wildlife
5. a stationary pollution source, a direct location
6. rarely found in drinking water but it contaminates water that passes through pipes
7. legislation that set national standards for drinking water
10. a source of pollution that is widely distributed and not from just one thing
13. a small sewage treatment system with a septic tank and a leach field
15. water that has been used for human toilets, businesses, and livestock
16. amount of dissolved oxygen needed in water for microorganisms to decompose organic matter
20. apart of the septic system and is pipes below the surface