Between the late 1940s and 1970, many major pollution problems got the public's attention. Extreme air pollution affected thousands in the United States and elsewhere. In the late 1960s, many beaches closed due to contamination from pollutants. An early oil spill off the California coast killed wildlife. Then in 1969, Americans watched news reports of Ohio's polluted Cuyahoga River catching fire and burning for days.
Both the public and government officials became more concerned about pollution. In 1972 the CWA or Clean Water Act passes in the United States. This act requires industries to reduce or eliminate point source pollution into surface waters. Industry was now accountable for their waste and sewage treatment plants were utilized to help remove raw sewage from America's waterways. Due in part to the CWA surface water pollution has dropped from the 1970s. Check out your area's water quality. The Safe Drinking Water Act of 1974 helped protect drinking resources. It set maximum contaminant levels of pollutants in drinking water.
I was going through my old bookmarks today and I came across this Treehugger post about Mountain Top Removal Coal mining. This process has to disrupt the layers of rock that filter the water.