4 WATER TESTS

CHAPTER 4 WATER TESTS After a sad and quiet lunch, Sassafras and I went back to the stream. I brought a cup for a water sample and my science journal. When we got there, I took out my journal and wrote: QUESTION:

Is our stream polluted? OBSERVATIONS: No mayfly babies. No caddisfly babies I bent over and scooped up some stream water with the cup. This time, I was careful not to get any water on my hands or feet. I tucked my journal under my arm, and Sassafras and I walked straight back home. We found Mom in her office with Dad. I handed her the water sample I'd carried home from the stream. "Thanks, sweetie. Do you want to help me?" I darted over to Mom's side. I was excited to help. And also a little scared of what the tests might tell us. I was just as worried about the stream bugs as I'd be about any magical animals. Now that I

thought about it, I hoped the polluted stream wasn't hurting the magical creatures in the forest too! "There's still a chance that the stream isn't polluted, right, Mom?" "Yes. We won't know until we run some tests." She put kits with tubes and little tablets on the counter. I peeked at the supplies. I loved when my mom let me use the same tools that real grown-up scientists use in their labs. I poked a finger at one of the shiny plastic cards with different colored squares. Mom looked down at me. "You're going to use real chemicals to test the water sample. So what do you need for your eyes?" "My Thinking Goggles!" I dashed to my room, grabbed my lucky goggles, and ran back to help my mom. I usually wore my Thinking Goggles on top of my head (close to my brain) to give me good ideas. But this time I used them in the usual way on the front of my face. Keep my eyes safe. Mom opened a tiny tube filled with little strips of paper. Let's test for ph first. Put on the gloves, then fill an empty test tube with some of the stream water Next, add a strip of paper and watch it. It will

change color after about a minute. Once the color stops changing, pull it out and match it to one of the colored squares on this card." I did all the things she said. It took me a minute to decide which square matched the color of the paper strip. "I'm pretty sure it matches square number ten. What does that mean, Mom?" Dad shook his head sadly. "It means that there's definitely something in our stream," Mom said. "A normal stream would be close to seven. Pollution can cause that number to go really low or really high, depending on what is being added. This is a clue, though. We know that whatever was added to the stream has a high pH number. Let's run one more test to see if we can guess what type of pollution it is."

She pulled out a new test tube. This time I got to put a tablet inside the tube and shake it. The stream water changed from clear to a pretty blue in the tube.

Mom and Dad both frowned when they saw the color. "It's testing positive for phosphates," Mom said to Dad. Then she turned to me. "These results definitely explain why you didn't see any mayfly or caddisfly nymphs. My best guess is that there's some kind of soap or detergent getting into our stream." I set the tube down with a frown and wrote in my science journal: