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Non-point source pollution arises when contaminants are carried into waterways by natural processes, like run-off or air currents. A common example is when run-off carries fertilizers from farms into waterways. Harder to pin-point - because the source covers a large land area - and more difficult to regulate than point-source pollution, especially because of the lack of explicit fault by any one person, non-point source pollution is a serious but insidious threat to ecosystem health. Examples of major contaminants include: !animas01.jpg!
Source: USGS and Barbara Hite
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