1. The granular filter media used to filter wastewater can become coated with a biological slime due to the _ in the wastewater.
d. soluble BOD and ammonia
2. One ton chlorine tanks _.
a. have fusible plugs located at valves
b. must be stored in an upright position
c. remove liquid chlorine from the top valve
d. use the bottom valve only with the chlorine evaporators
3. If a generator will not start, check for _.
a. loose terminal connections
b. shaft binding or sticking
c. tripped circuit breakers
d. all of the above
4. The most abundant source of pollutants entering natural water bodies (rivers, lakes) is _.
a. domestic waste
b. food processing waste
5. The most critical criterion for determining when a mixed media filter should be backwashed is _.
a. filter effluent quality
b. flow rate
c. head loss
d. visual inspection of the filter surface