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runoff – n. water from rain or snow that flows over the surface of the ground into streams; water from cities that flows into the ocean
contamination – n. the state of being dangerous, dirty or impure because something harmful or undesirable has been added
sewage – n. waste material that is carried away from homes and other buildings in pipes
terminate – v. to end in a given way or at a particular place
outdated – adj. no longer useful or acceptable
ridiculous – adj. extremely silly or unreasonable
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