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TEXAS WASTEWATER C LASS A NEWEST 2024-2025
ACTUAL EXAM COMPLETE 200 QESTIONS AND
CORRECT DETA ILED ANSWERS (VERIFIED
ANSWERS) |ALREADY GRADED A+
Why is recirculation needed in a trickling filter? - ANSWER- a.Keep the media wet b. Further reduce BOD c. Flood the filter to control ponding and filter flies
- What type of fire extinguisher would be used on an electrical
control panel that has been de-energized? - ANSWER- f. a class a and d class c
Disinfection with chlorine is the most effective at a pH of -
ANSWER- 6.0
- The biomass on a normal functioning RBC has what
appearance? - ANSWER- Grey to brown and 0.05 to 0.1 inch thick
The sludge from a primary clarifier should contain what percent solids? - ANSWER- b. 4% to 6%
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What is eutrophication in a pond system? - ANSWER- Enrichment with nitrogen and phosphorous Causes algae blooms
- A wastewater stabilization pond has 130,680 sq. ft. It has a
three to one slope on the embankment and has an average depth of 5 ft. Approximately how many people will this pond provide wastewater treatment for? 130,680 sq ft = 3 acres x 35 lbs / BOD/ acre = 105 lbs BOD =618 0.17 lbs BOD/ person 43,560 sq ft l acre - ANSWER- d. 600
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- Indirect; 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 2 / 4
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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
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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
trench is 4,100 feet long, four 4 wide and 6 feet deep. There is a 12-inch diameter pipe in the bottom of the trench. How many cubic yards of material were removed from the trench?4x6x4,100 3,644 27 - ANSWER- 3,644
In the problem above, how many cubic yards of material will be required to fill the trench? 3.14x0.5 x0.5 x 4,100 =119cu yds 27
3,644 -119 = 3,525 - ANSWER- 3,525
What is the standard chlorine residual and contact time on Texas discharge permits? - ANSWER- e. None of the above organization increases,
As the complexity of an organization increases, what management function becomes most important? - ANSWER- Planning
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