1. BOD is a term that refers to the _.
a. oxygen demand in milliliters per hour per square meter of lagoon surface during the aerobic phase of metabolism
b. oxygen required to neutralize the effects of anaerobic organisms in wastewater effluents
c. oxygen required to stabilize the decomposable organic matter in a wastewater sample by bacterial action
d. phase of the nitrogen cycle known as anabolism or synthesis

2. Which of the following types of pumps is not found in raw sewage lift stations?
a. pneumatic ejector
b. centrifugal
c. submersible
d. positive displacement

3. Copper sulfate-sulfamic acid solution is added to a sample of mixed liquor on which a D.O. test is run in order to _.
a. prevent settling of the sludge while the sample is in transit to the laboratory
b. keep the organic process at a high level while the sample is in transit to the laboratory
c. kill the bacteria which would continue to use oxygen while the sample is in transit to the laboratory

4. The simplest chemical form of phosphorus produced by persulfate digestion is _.
a. orthophosphate phosphorus
b. hydrolyzable phosphorus
c. organic phosphorus
d. polyphosphate phosphorus

5. The heating value (BTU/cuft) of a normal digester gas is _ natural gas.
a. less than
b. more than
c. equal to

Answers:

1. c
2. d
3. c
4. a
5. a