AWWA Wastewater 4 Study Guide with Complete Solutions.
What is the odor detection limit of chlorine gas? correct answers 0.3 ppm
What is a cathode? correct answers negative pole of an electrolytic cell or system
The least reactive metals are called correct answers cathodic metals
Unless water cooled, the operating temperature of a mechanical seal in a pump should never
exceed correct answers 160 F or 71 C
What term describes the condition that exists when the source of the water supply is below the
centerline of the pump correct answers suction lift
All occupied trenches 4 or more feet deep must provide exits at correct answers 25 ft intervals
What is the difference between a weak acid and a strong acid? correct answers amount of
hydrogen ions released
What is the best type of valve to use to dampen a water hammer? correct answers pressure-relief
What does the term stray-current corrosion mean? correct answers decomposition of a material
caused by an outside electric current
A shock load of toxic wastes coming into a plant can be treated or controlled with correct
answers coagulants or chlorine
Toxic solids should be disposed of in correct answers an approved sanitary landfill
On startup of a small package wastewater treatment plant, lime should be added to the digestion
unit when the pH goes below correct answers 7.0
If the effluent to a small package wastewater treatment plant using the activated sludge process
appears turbid, what is most likely the cause? correct answers pumping rate for the return of
activated sludge is out of balance
If a small package treatment plant utilizing the activated sludge process has a light colored
floating sludge on the surface of the clarifier, which of the following would eliminate the floating
sludge? correct answers reduce the aeration rates
What usually causes frothing in the activated sludge process? correct answers too long a
detention time
What would control foaming? correct answers water sprays
What is the odor detection limit of chlorine gas? correct answers 0.3 ppm
What is a cathode? correct answers negative pole of an electrolytic cell or system
The least reactive metals are called correct answers cathodic metals
Unless water cooled, the operating temperature of a mechanical seal in a pump should never
exceed correct answers 160 F or 71 C
What term describes the condition that exists when the source of the water supply is below the
centerline of the pump correct answers suction lift
All occupied trenches 4 or more feet deep must provide exits at correct answers 25 ft intervals
What is the difference between a weak acid and a strong acid? correct answers amount of
hydrogen ions released
What is the best type of valve to use to dampen a water hammer? correct answers pressure-relief
What does the term stray-current corrosion mean? correct answers decomposition of a material
caused by an outside electric current
A shock load of toxic wastes coming into a plant can be treated or controlled with correct
answers coagulants or chlorine
Toxic solids should be disposed of in correct answers an approved sanitary landfill
On startup of a small package wastewater treatment plant, lime should be added to the digestion
unit when the pH goes below correct answers 7.0
If the effluent to a small package wastewater treatment plant using the activated sludge process
appears turbid, what is most likely the cause? correct answers pumping rate for the return of
activated sludge is out of balance
If a small package treatment plant utilizing the activated sludge process has a light colored
floating sludge on the surface of the clarifier, which of the following would eliminate the floating
sludge? correct answers reduce the aeration rates
What usually causes frothing in the activated sludge process? correct answers too long a
detention time
What would control foaming? correct answers water sprays
