A clarifier is 75 ft in diameter and 11 ft deep. Determine the volume of the clarifier in gallons.
What is 363,318 gallons?
100
A check valve placed on the bottom of the suction side of a pump, which opens to allow water to enter the suction side of the pipe. Holds the prime.
What is a foot valve?
100
If operators are scheduled to work in a manhole how often should the atmoshere in the manhole be tested.
What is continuously?
200
In order for a BOD test to be considered valid, the dissolved oxygen content in the blanks can not be deplete more than ____ mg/L during the 5 day incubation period.
What is 0.2 mg/L ?
200
The addition of chlorine gas to wastewater will cause the pH to_____. (increase or decrease).
What is decrease?
200
A clarifier holds 1 MG and has a flow of 8,000,000 gpd, determine the detention time in hours
What is 3 hours?
200
A perforated ring placed around the pump shaft in the stuffing box. Water from the pump discharge is piped tothis ring. The water forms a liquid seal around the shaft and lubricates the packing
What is a lantern ring?
200
Before beginning work on a pump or motor the first thing that should be done is_____.
What is lock out /tag out?
300
The two most common ways to measure chlorine residual.
What are amperometric tiration and DPD?
300
The point at which the chlorine dose has met the chlorine demand and any additional chlorine added will form a residual.
What is breakpoint?
300
A weir on a clarifier is 350 ft long. The flow through the clarifier is 3 MGD. Determine the weir overflow rate in gpd per foot of weir length.
What is 8571.4 gpd/ft?
300
The most common pump driver used in lift stations.
What is an AC induction motor?
300
An atmospheric test unit should be able to detect flammable, explosive, and toxic gases as well as this______.
What is oxygen deficiency?
400
The capacity of water to neutralize a strong acid, due to the presence of carbonates, bicarbonates and hydroxide.
What is alkalinity?
400
Name a compound that can be used to dechlorintate wastewater.
What are sulfur dioxide, sodium sulfite, sodium bisulfate, sodium thiosulfate?
400
A circular primary clarifier has a diameter of 60 ft. The influent flow to the clarifier is 2.62MGD. Determine the surface overflow rate in gpd/sq. ft?
What is 927 gpd/sq. ft?
400
The purpose of packing.
What is to keep air from entering and to keep water from leaking out.
400
This type of fire extinguisher should be used on electrical fires.
What is Class C (carbon dioxide)?
500
The two approved methods for measuring dissolved oxygen.
What are the winkler tiration and the DO probe/meter?
500
Chlorine contact chambers shall be sized to provide a minumum of ____ minutes detention time at average design flows.
What is 30 minutes?.
500
The influent BOD concentration to a primary clarifier is 190 mg/L and the primary effluent BOD is 100 mg/L.
Determine the efficiency of the clarifier in percent.
What is 47.3%?
500
The purpose of lubrication.
What is to reduce friction and reduce heat being produced by the friction.