COMPREHENSIVE TEST PAPER 2026
COMPLETE QUESTIONS AND ANSWERS
EXPERT VERIFIED GRADED A+
◉ The sludge from a primary clarifier should contain what percent
solids? Answer: 4% to 6%
◉ What is eutrophication in a pond system? Answer: Enrichment
with nitrogen and phosphorous Causes algae blooms
◉ A"Racetrack" is what type of Activate Sludge treatment? Answer:
Extended air
◉ Which form of activated sludge must have primary clarifiers?
Answer: Conventional
◉ What is the relationship between F M ratio and MCRT? Answer: if
one goes up, the other goes down
◉ Which activated sludge process does not achieve complete
nitrification? Answer: Contact stabilization
,◉ Which form of activated sludge does the better job of handling
shock or toxic loads? Answer: Complete mix
◉ Which of activated sludge has two aeration basins per single
treatment unit? Answer: Contact stabilization
◉ A complete mix activated sludge plant has a fast settling sludge
and high amounts of pin floc leaving the clarifier. One method of
correcting the problem is to Answer: Increase F/M ratio by wasting
more
◉ problem is Testing of mixed liquor indicates the MLSS is 2500
mg/L and the settling test shows that a 1000 ml sample settles to
400 mls after 30 minutes. What is the SVI? 400 x 1000 2500 160
Answer: 160
◉ In the problem above, what the sludge quality? Answer: Bulking
◉ Which activated sludge process has 18 to 20 + hours detention
time in the aeration basin? Answer: Extended air
◉ What is the minimum clearance from the sidewall of a pipe to the
trench wall in an excavation? Answer: 4 inches
, ◉ What is the definition of pH? Answer: The logarithm of the
reciprocal of the hydrogen ion concentration The negative logarithm
of the hydrogen ion concentration
◉ How often should pH meters be calibrated? Answer: Daily
◉ As the complexity of an organization increases, what management
function becomes most important? Answer: Planning
◉ When chlorinating treated wastewater, what chlorine residual do
we test for? Answer: Chloramine and Total
◉ What is the standard pH range on Texas effluent discharge
permits? Answer: . 6.0 to 9.0
◉ In Texas, an oxidation ditch treatment plant is referred to as
Answer: Racetrack
◉ In Texas, pH meters are required to be calibrated on how many
buffers? Answer: two
◉ An industrial complex has a BOD discharge to the POTW of 500
pounds per population equivalent of this industry is Answer: 500 lbs
- 2,941 0.17 lbs BOD/ person 2941