With your help, the Fruitvale Water Department was able to locate the contaminant source in Fruitvale.  Yet you learned that locating the source is just the beginning of figuring out what to do about the problem.  The next step is to monitor the wells regularly to see if the contamination continues to spread.  If it is spreading the water department will need to figure out how fast it is spreading.  The faster it spreads, the more problems it can create.  In order to determine the spreading rate, the Fruitvale City Council authorized a second round of well testing, one year after the original tests that were conducted with your help.

A year later you return to Fruitvale for an internship with the water department.  You assist with the second round of testing.  You are going to use data from this second round of testing to determine how fast the pesticide is spreading through Fruitvale’s aquifer. 

4.  Look at the map of wells for one year on.  Draw the plume containing the contamination level 3.

5. Measure the shortest distance between the plue line and the Fruitvale Municipal well after 1 year.  How far in actual distance is the leading edge of the plume from the Fruitvale Municipal Water well now?

6. Determine the monthly rate of spread by dividing the change in position of the plume for contamination 3 by 12 months.

7. When do you predict the pesticide will reach the Fruitvale Municipal Water Well?  Explain your answer.