Contaminants • contaminant: an undesirable substance in a mixture • Where do they come from?
Chemical Fertilizers Herbicides Pesticides Salt Minerals Acid Rain Other chemicals Biological Micro-organisms Organic Matter Types of Contaminants
Contaminants in Fresh Water • Contaminants in Water.doc
Walkerton Crisis • http://www.cbc.ca/news/background/walkerton/walkerton_report.html
Acid Rain Video • http://www.youtube.com/watch?v=WOHJXyhe2Tk&safety_mode=true&persist_safety_mode=1&safe=active
Endangering Animals • http://www.youtube.com/watch?v=Ku5dgUtXcLo&safety_mode=true&persist_safety_mode=1&safe=active
Check Your Learning • 1. Name two parts of the water cycle in which contaminants can be introduced. • 2. (a) What are the two main categories of contaminants in water? • (b) Why are they a problem? • 3. Choose two chemical contaminants that could be found in a freshwater source. For each one, • (a) identify a source of the contaminant • (b) describe how the contaminant got into the water • 4. Briefly describe how a biological contaminant was able to get into groundwater wells at Walkerton.