Soil Saturation and Pollution Science Fair Projects

Soil Pollution

Soil pollution is problem that we all need to be aware of. It is more commonly referred to as soil contamination. There are many substances that can pollute soil including toxic runoff, fertilizers and even laundry detergent.

PURPOSE

The purpose of this experiment was to determine which polypedon (type of soil) was most absorbent of liquid pollutants.

I became interested in this idea when I was playing in a creek near my Grandma's house. I noticed that the soil around the creek was darker and smelled funny. I moved several rocks that also smelled strange on the bottoms to find soil saturated in oil. I thought that if the oil had drifted downstream then the entire creek banks would be polluted. I then wondered that if the soil around the creek banks were less absorbent if they would be less polluted.

The information gained from this experiment will benefit farmers, gardeners and botanists who have soil pollution problems to better understand absorbency in different types of soil.

HYPOTHESIS

My first hypothesis was that the soil with less porosity would be most absorbent.

My second hypothesis was that the more viscous pollutant would be most absorbent.

I based my first hypothesis on the fact that soil with less porosity will have less room for liquids to fill, making the soil allow liquids to sit on top for a period of time.

I based my second hypothesis on Troy Slobig's statement, which was "Since oil is thicker than gas and antifreeze, it should be absorbed the most."

EXPERIMENT DESIGN

The constants in this study were:

• The filter used
• Amount of pollutants (250 ml)
• Amount of soil filtered (250 mg)
• Number of trials on 1 soil type with 1 kind of pollutant (3)
• Temperature of pollutants (21°C )

The responding variable was the amount of pollutants that filtered through the 250 mg of soil.

To measure the responding variable I used a graduated cylinder mL.

MATERIALS

PROCEDURES

1.) Create a clean and organized area near a working sink or tub of water.
2.) Place 1 plastic cup on the table.
3.) Set filter in the cup so it is sturdy.
4.) Carefully put 250mg of soil 1 in filter.
5.) Accurately measure 250mL of oil in a graduated cylinder.
6.) Pour oil onto soil 1 slowly and steadily.
7.) Once oil is completely out of the cylinder begin timing filtering for 60 seconds with the stopwatch.
8.) After the 60 seconds are completed, immediately remove filter from the cup and set it in the sink. Immediately clean up any spills if you have any.
9.) Once the filter is in the sink pour the remaining oil in the cup, into the graduated cylinder. Record the amount on the piece of scratch paper, but this is not your final measurement.
10.) On the same paper as the recorded measurement, write the following equation: 250 - pollutants remaining = pollutants absorbed, and solve it by filling in the numbers where the variables are.
11.) Record the difference to the equation in step 10 on the organized table.
12.) Repeat steps 1-11 two times with the same pollutant and the same soil.
13.) Repeat steps 1-11 three times with the same pollutant and soil 2.
14.) Repeat steps 1-11 three times with gasoline and soils 1 and 2.
15.) Repeat steps 1-11 three times with antifreeze and soils 1 and 2.

RESULTS

The original purpose of this experiment was to determine which polyp don (type of soil) was most absorbent of liquid pollutants.

The results of the experiment were that the oil and clay combination was the most absorbent as I suspected, but some oil just sat on the top because it was so thick. The clay absorbed an average of 220.33mL of oil, 112.33mL of antifreeze, and 132.33mL of gasoline. The sand absorbed an average of 126mL of oil, 146.33mL of antifreeze and 138mL of gasoline. I noticed that the antifreeze and gasoline ran right through both soils quickly because they were both thin, like water.

CONCLUSION

My first hypothesis was that the soil with less porosity would be most absorbent.

My second hypothesis was that the more viscous pollutant would be most absorbent.

The results indicate that my first hypothesis should be accepted.

The results also indicate that my second hypothesis should be accepted.

Because of the results of this experiment, I wonder if the moisture of the soil affected its ability to drain and absorb liquids.

If I were to conduct this project again I would use a wider variety of pollutants and kinds of soil, more accurately measure my data with more accurate tools, do more trials on the experiment and follow my procedures more closely and accurately.