What proof do you see that contaminated water seeped into the well? How could scientists use a similar approach to understand wa
tershed in a community? Emmerson is making a model of a well. He places screen material into a vase. On one side, he adds a layer of aquarium gravel and then tops it with soil. These layers model the rock and soil layers outside the well. Emmerson leaves the space on the other side of the screen empty to model the inside of the well.
