Goals • 1) Determine the source of contamination. • 2) Determine the entire “plume” of contamination. • 3) Draw lines on the map connecting areas of equal contamination.
Procedure • 1) Due to the budget you will be allowed to test three well sites. Before testing your group needs to tell Mr. Robinson which sites and why you decided on those three. • 2) Test your three sites, if approved by Mr. Robinson. Do not share data with other groups. • 3) Determine 3 more sites to test and get approval from Mr. Robinson. • 4) After you have completed a total of 6 tests report your findings to Mr. Robinson. If further testing is needed he may allow for 2 more tests.
How to test • Place 1 mL of your water sample in one of the reaction plate wells. • Add one drop of indicator solution to the sample. • Use a toothpick to stir the solution in the well. • Add the testing solution dropwise, using the toothpick to swirl after each drop. • Count the drops as they are added until the color changes from yellow to purple irreversibly. • Record the drop count on the data sheet and ppb on map.
1 to 2 drops 0-10 ppb • 3 to 5 drops 25 ppb • 6 to 12 drops 50 ppb • 13 drops or more 200 ppb