Well let's start off with pollution. Pollution is the effect that humans have by littering in natural sources of water such as ocean water. Ground water on the other hand is the natural water found deep below the Earth's surface.
Here's an example. In Florida, due to the geography being flat (sea level),most of the time when something is dug up, water is found. That's your groundwater.
But things like oil spills are pollution. Sometimes, these pollutants can sink into the natural ground water and harm it. These can have bad effects on people. Things such as Fiji Water is found from aquifers that take drinking water from ground water. If someone was to drink this water, huge recalls and many people getting sick can also happen.
Hope this helped you out.
