1. Understanding the basis of water pollution.

2. 1. Placing unwanted substances (pollutants) into the ecosystem 2. Pollution has negative impact on living things 3. Ex. Oil, trash, human/animal wastes, nuclear wastes from factories, acid rain, etc. 4. Sources of pollution: human activity, natural causes

3. 1. Point source pollution: the place where the pollution originates can be identified 2. Nonpoint source pollution: the origin of pollution can not be identified easily

4. 1. Point source pollution: septic sewage tank; damaged sewer pipes, release of raw sewage from wastewater treatment plants 2. Nonpoint source pollution: runoff near a lake or stream, waste runoff from feedlots, runoff from streets (sand, grit, oil, & gasoline)

5. 1. Disease-causing organisms (Cryptosporidium); caused by human wastes & runoff livestock pens 2. Pesticides & fertilizers: DDT, nitrates, phosphates caused by runoff from farms fields, golf courses 3. Industrial chemicals: PCBs, carbon tetrachloride, dioxin caused by factories & waste disposal sites

6.  5. Radioactive wastes such as uranium and carbon-14 caused by medical & scientific disposal sites & nuclear power plants  6. Petroleum products such as oil, gasoline caused by road runoff, leaking & underground storage tanks  Log on to Edmodo.com and answer the following question: Why might it be helpful to know the source of a particular pollutant detected in a body of water?