WATER POLLUTION. Contaminant vs. Pollutant. Contaminant- any constituent in the water that is harmful to its end use. (radon, coliform bacteria from animals, arsenic & other metals naturally in rock/soil)
Any chemical, biological and physical change in water quality that has a harmful effect on living organisms or makes it unusable for agriculture
Discharged from a specific location
Usually from a pipe directly into water
Sources identifiable which makes it easier to monitor & regulate
EX: factories, sewage treatment plants, coal mines, oil wells
Discharged from scattered or diffuse locations
No specific location where the discharge came from
Harder to monitor & regulate; may be episodic
1st heavy rainfall washes lots of gas, oil, trash into river
EX: runoff from feedlots, farm fields, golf courses, lawns, construction sites, logging areas, streets, parking lots, atmospheric deposition (grasshopper effect)Point vs. Non-Point Pollution
All streams have some capability to degrade organic waste. Problems occur when stream is overloaded with biochemical oxygen-demanding waste.
Thermal PollutionThis 1988 thermal image of the Hudson River highlights temperature changes caused by discharge of 2.5 billion gallons of water each day from the Indian Point power plant. The plant sits in the upper right of the photo — hot water in the discharge canal is visible in yellow and red, spreading and cooling across the entire width of the river. Two additional outflows from the Lovett coal-fired power plant are also clearly visible against the natural temperature of the water, in green and blue.