Turbidity

PURPOSE= To test the level of turbidity in the grand river to see if recyucleing at lunch will help lower that level.

RESEARCH= The high schools trash is only picked up one to two times a week and when the dumpster is overfull and it rains the water runs through the rotten food at the bottom of the dumpster and the water is washed away through a pipe that is directly connected to the Grand River.

HYPOTHESIS= If the rain water waiste from the high schools garbage runs into the Grand River then there will be a high turbidity

MATERIALS= 60 mL standard Turbidity Reagent
2 Turbidity Columns
1 brush, test tube
1 Pipet, 0.5 mL, plastic, w/cap
1 Rod, pastic, stirring

PROCEDURE= 1: Fill one Turbidity Column to the 50 mL line with the sample water. If the black dot on the bottom of the tube is not visible when looking down through the column of liquid, pour out a sufficient amount of the test sample so that the tube is filled to the 25 mL line
2: Fill the second Turbidity Column with an amount of turbidity-free water that is equal to the amount of sample being measured. Distilled water is preferred; however, clear tap water may be used. This is the "clear water" tube.

3: Place the two tubes side by side and note the difference in clarity. If the black dot is equally clear in both tubes, the turbidity is zero. If the black dot in the sample tube is less clear, proceed to Step 4.

4: shake the Standard Turbidity Reagent vigorously. Add 0.5 mL to the "clear water" tube. Use the stirring rod to stir contents of both tubes to equally distribute turbid particles. Check for amount of Turbidity by looking down at the solution at the black dot. If the turbidity of the sample water is greater than that of the "clear water", continue to add Standard Turbidity Reagent in 0.5 mL increments to the "clear water" tube, mixing after each addition until the turbidity equals that of the sample. Record total amount of reagent addeed.

5:Each 0.5 mL addition to the 50 mL size sample is equal to 5 Jackson Turbidity Units (JTUs). If a 25 mL sample size is used, each 0.5 mL addition of the Standard Turbidity Reagent is equal to 10 Jackson Turbidity Units (JTU's). Rinse both tubes carefully after each determination.