Your tank measures 100 ft in diameter and is 12 ft deep. How many gallons will the tank hold when full?
a. 704,616 gallons
b. 710,000 gallons
c. 94,200 gallons
What is (A) 704,616 gallons
The flow velocity in a sanitary sewer is _____ fps?
a. 2.0 fps
b. 1.0 fps
c. 0.33 fps
d. 2.5 fps
What is (A) 2.0 fps
What device is more commonly used for separation of grit slurry?
What is (C) Cyclone
What portion of the wastewater treatment process is generally regarded as protecting the downstream equipment?
A) Preliminary treatment
B) Primary treatment
C) Secondary Treatment
What is (A) preliminary treatment
What is the equivalent in mgd for 78,850 gpd?
What is (3) 0.07885 mid
Which bar screen will capture more debris on its screen?
What is (2) the bar screen that runs on either timer control or level control
Your tank measures 100 feet wide, 30 feet wide, and 10 feet deep. What is the total surface area in sq ft?
a. 30,000 sqft
b. 3,000 sqft
c. 1000 soft
What is (A) 30,000 soft
The 5 causes of White Billowing Foam are:
1.__________
2._________
3.__________
4._____________
5._____________
What is:
Plant start up; Toxic; Hydraulic Washout; improper wasting; improper return
Fresh “domestic” wastewater is characterized by:
What is (A) dishwater gray color and slight odor
Which type of bacteria must have free dissolved oxygen to survive?
1. Anaerobic
2. Anoxic
3. Facultative
4. Aerobic
What is (4) Aerobic
What does H2S smell like at high concentrations?
What is (3) no smell
What is the surface area of the secondary clarifier?
• Secondary Clarifier Diameter is 50 ft. and the Depth is 12 ft. (Daily Double)!!!!!
What is (4) 1,963 square feet
Estimate the velocity in a grit channel in fps if a stick travels 50 feet in 40 second?
a. 12.5 fps
b. 1.25 fps
c. 2000 fps
d. 0.8 fps
What is (B) 1.25 fps
The heavy material present in wastewater such as sand, coffee grounds, eggshells, gravel and cinders.
What is (C) detritus
Pathogens are defined as ___________ bacteria:
What is (D) disease causing
What is an intermediate oxidation state between ammonia nitrogen (NH3) and nitrate nitrogen (NO3)?
What is (4) NO2
What happens to the alkalinity in wastewater during the denitrification process?
What is (1) it increases
What is the makeup of typical grit debris?
What is (3) inorganic material
(Daily Double)!!!
What are the 4 classifications (types) of wastewater entering the wastewater plant through the sewer system?
What is:
Organic
Inorganic
Radioactive
Industrial
How is grit removed ?
What is (D) reducing the velocity of the wastewater from 2.0 fps to 1.0 fps
What is the purpose of a stilling well?
What is (A) dampens surges and allows a well's water level to fluctuate in a flow channel
Which dangerous gas will be more likely to rise near the surface of a manhole?
What is (2) Methane
What is the makeup of typical screenings debris?
What is (1) Organic material
What happens to the alkalinity in wastewater during the nitrification process?
What is (2) it decreases
How many cubic feet of screenings are removed per million gallons of flow when the plant has an average flow rate of 6 million gallons and 400 gallons of screenings are removed each day?
What is 9.0 cubic feet per million gallons
400 / 7.48 = 53 cuft
53 / 6mgd = 9.0 cuft
Aerated grit chambers usually utilize what type of aeration system?
What is (B) Diffused
In a clarifier, the sludge that forms at the bottom may be referred to as the:
a. Sludge cover b. Sludge level
c. Sludge blanket d. Waste sludge
What is (C) sludge blanket
What is the amount of oxygen required to convert 1 ppm of ammonia-nitrogen?
What is (3) 4.6 lbs
Which best describes the nitrification cycle?
1. ammonia is converted to nitrates then to nitrites
2. ammonia is converted to nitrites to nitrates
3. nitrates is converted to ammonia then nitrites
4. nitrites is converted to ammonia then nitrogen
What is (2) ammonia is converted to nitrites and then to nitrates
Which of the following is considered to be the least harmful bacteria?
What is (2) fecal coliform