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Wastewater Class 4 Exam Virginia Questions with 100%
Verified Answers UPDATED!!!
In an electrical circuit, the grounding wire is indicated by which
color? - ANSWER Green
According to the Ohms Law, which electrical unit measures
pressure? - ANSWER Volts
According to the Ohms Law, which electrical unit measures
resistance? - ANSWER Ohms
According to the Ohms Law, which electrical unit measures
current? - ANSWER Amps
How do you convert cubic feet to gallons? - ANSWER Multiply
by 7.48
How do you convert gallons to pounds? - ANSWER Multiply by
8.34
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Calculate the SVI of your aeration basin when your 30-minute
settleable sample is 360 mL/L and your average mixed liquor
suspended solids concentration is 4000 mg/L. - ANSWER 90
Solution:
360 x 1,000
------------- = 90
4,000
What is the most widely used dechlorination agent in a
conventional chlorine gas plant? - ANSWER Sulfur Dioxide
What is the most prominent concern in failing to remove grit
from the wastewater? - ANSWER Excessive wear and damage
on mechanical equipment
What is the chemical formula for Sulfuric Acid? - ANSWER
H2SO4
What is the ideal velocity in a grit channel, in feet per second? -
ANSWER 1 fps
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Conventional pump packing should be: - ANSWER Tightened
down to a drip
In a primary clarifier, the expected performance for removing
settleable solids is 90-95% removal. What about the removal of
suspended solids? - ANSWER 50%
When preparing a sample for laboratory analysis that involves
acid and water, how should the sample be poured? - ANSWER
Always pour the acid into the water
You are tasked with recording a manual flow sample in an open
channel. Where will you position yourself, relative to the weir,
to record the most accurate measure of flow? - ANSWER Behind
the weir, 4 times the maximum head of the weir
Why must a positive displacement pump never be started
against a closed discharge valve? - ANSWER Excessive pressure
may damage the line, the pump, and the motor
Wastewater Class 4 Exam Virginia Questions with 100%
Verified Answers UPDATED!!!
In an electrical circuit, the grounding wire is indicated by which
color? - ANSWER Green
According to the Ohms Law, which electrical unit measures
pressure? - ANSWER Volts
According to the Ohms Law, which electrical unit measures
resistance? - ANSWER Ohms
According to the Ohms Law, which electrical unit measures
current? - ANSWER Amps
How do you convert cubic feet to gallons? - ANSWER Multiply
by 7.48
How do you convert gallons to pounds? - ANSWER Multiply by
8.34
,2|Page
Calculate the SVI of your aeration basin when your 30-minute
settleable sample is 360 mL/L and your average mixed liquor
suspended solids concentration is 4000 mg/L. - ANSWER 90
Solution:
360 x 1,000
------------- = 90
4,000
What is the most widely used dechlorination agent in a
conventional chlorine gas plant? - ANSWER Sulfur Dioxide
What is the most prominent concern in failing to remove grit
from the wastewater? - ANSWER Excessive wear and damage
on mechanical equipment
What is the chemical formula for Sulfuric Acid? - ANSWER
H2SO4
What is the ideal velocity in a grit channel, in feet per second? -
ANSWER 1 fps
, 3|Page
Conventional pump packing should be: - ANSWER Tightened
down to a drip
In a primary clarifier, the expected performance for removing
settleable solids is 90-95% removal. What about the removal of
suspended solids? - ANSWER 50%
When preparing a sample for laboratory analysis that involves
acid and water, how should the sample be poured? - ANSWER
Always pour the acid into the water
You are tasked with recording a manual flow sample in an open
channel. Where will you position yourself, relative to the weir,
to record the most accurate measure of flow? - ANSWER Behind
the weir, 4 times the maximum head of the weir
Why must a positive displacement pump never be started
against a closed discharge valve? - ANSWER Excessive pressure
may damage the line, the pump, and the motor
