It’s Water-Wise Wednesdays with Frannie the Fish! {Awesome Aquifer Kit: Contamination Clues}

This week in Frannie’s exploration of the Awesome Aquifer Kit is all about how contamination can affect groundwater and surface water systems.

For this activity, you will need the clear container filled with gravel,
"clean" blue water, "contaminated" red water, 2 pumps, and an empty
cup to collect the "polluted" water.

There are many chemicals that we use every day that are helpful to our lives but, if we drank them, could really hurt us.  Farmers use pesticides and fertilizers to help their crops grow healthy and strong.  Cities and people at home use de-icers or sand to keep the roads safe to drive on in the winter.  When we are careful, the environment is safe.  If we make a mistake with those chemicals, we might pollute the area and affect the whole region around us.  Let’s see how that happens.

In our clear container with evenly spread gravel, we can add water until about half of the gravel is saturated.  Let’s make a lake in the middle of the container by scooping the gravel to the sides and on top of each hill, we’ll put one well.  One well will be a monitoring well, meaning we’ll only withdraw water samples from it.  The other well represents a functional well that provides water for drinking.

We’ll fill a small measuring cup with water and add 2-4 drops of food dye.  By doing this, we can clearly see which water is contaminated and which water is clean.  In a corner of our container, not too close to a well, we’ll slowly pour in our contaminant.  Watch as it infiltrates the system.

Top: Contaminated water infiltrates into the groundwater.
Bottom: Groundwater flow spreads the pollution through the
groundwater and even can affect surface water.

Now let’s start pumping the well that’s on the hill opposite of the contaminant.  That’s our drinking water well.  Can you see what’s happening to the contaminant?  When a contaminant spreads out away from its source, we call it a plume. The plume has started to move towards the drinking water well.  Collect this water in a separate container and save it.

Finally, let’s collect and save a water sample from our monitoring well (the one closest to the contaminant).  The color in this water is very different from what it was when we started.  We can easily see this water is contaminated.

Frannie compares the color of the water at the beginning
 to the color of the contaminated water.