EXERCISES, LESSON 6
INSTRUCTIONS: Answer the following exercises by marking the lettered response that
best answers the exercise, by completing the statement, or by writing the answer in the
space provided at the end of the exercise.
After you have completed all the exercises, turn to "Solutions to Exercises" at the
end of the lesson and check your answers. For each exercise answered incorrectly,
reread the material referenced with the solution.
Surface waters are contaminated primariIy by:
a. Surface runoff.
b. Seepage into artesion aquifers.
Percolation through the soiI.
d. Air pollution adhering to raindrops.
If a water source is only 4 inches deep, the intake strainer should be placed:
a. On the bottom.
b. On the surface (by means of a float).
In a pit dug in the bottom and Iined with sand.
d. In a pit dug in the bottom and Iined with coarse gravel or rocks.
Muddy, or turbid water may be improved in quality by the use of:
a. An intake strainer.
b. An intake gallery.
A diatomite fiIter.
d. A water softener.