QUESTIONS WITH DETAILED VERIFIED
ANSWERS 100 PERCENT CORRECT ANSWERS
ALREADY GRADED A PLUS
◉The term pathogenic means . Answer: Capable of causing disease
◉The minimum separation between sewer lines and potable water lines
is . Answer: 9 feet
◉A licensed wastewater operator is a professional . Answer: consistently
does best job possible, practices personal safety, strives to improve job
knowledge, strives to keep the plant and collection system in the best
appearance and working order
◉An important step in testing a
sample for Total Suspended Solids is . Answer: Filtering a sample
◉The Biochemical oxygen Demand (BOD) of a sample is based on .
Answer: Measuring the dissolved oxygen (DO) used
,◉The results of Biochemical Oxygen Demand (BOD)
sample taken at a treatment plant tells the operator . Answer: How the
plant was operating 5 days ago
◉Which of the following are dangerous gasses that are
likely to be present in lift stations and manholes? . Answer: Natural gas,
gasoline fumes, hydrogen sulfide and carbon dioxide
◉A preferred hydraulic method of cleaning sewer lines is . Answer:
Hydro Jet Cleaner
◉Ways to reduce bad odors coming from a collection system . Answer:
routinely cleaning slow running or low flow lines, adding chlorine or
hydrogen peroxide to the collection system
◉Types of pipe that are commonly used in
wastewater collection system . Answer: ductile iron, Poly Vinyl Chloride
(PVC)
◉Before entering a confined space a worker should . Answer: Use
approved monitoring device and check for the presence of dangerous
gasses, ventilate the space with a blower, wear a safety harness and
attach a life line
,◉A properly designed and operated primary sedimentation
tank should remove _____ percent of incoming BOD . Answer: 30-40%
◉Devices that may be used to determine the level of sewage in a lift
station . Answer: air bubbler, floats, electrodes, Acoustic (sonic)
◉What is the most important role of aerobic bacteria in the treatment of
wastewater? . Answer: decompose organic matter
◉The hydraulic loading of a trickling filter may be determined by .
Answer: flow rate and filter area
◉These can be used to dewater sludge . Answer: belt press, drying beds,
solid bowl centrifuge, gravity thickener
◉Most important to providing adequate
sewage treatment in a stabilization pond . Answer: sunlight, algae,
bacteria and time
◉Offensive and objectionable odors which
sometimes occur in trickling filters usually indicate . Answer: septic
conditions are present
◉Dissolved Oxygen (DO) in aeration tank of an activated
, sludge plant should be maintained at or about . Answer: 2 to 4 mg/L
◉Contributes to the infiltration in a collection system . Answer: breaks
in the main lines, high ground water levels, heavy rains, hydro jet
cleaning plugged mains
◉When a centrifuge pump loses prime the . Answer: pump is no longer
moving liquid
◉A Rotating Biological Contactor (RBC) is . Answer: fixed firm
biological treatment process
◉Needs to be checked regularly to properly
operate an activated sludge treatment plant . Answer: aeration equipment
and mixed liquor solids
◉Point source discharges are . Answer: discharges that come from pipes
or ditches that are monitored, controlled and inspected
◉Non-point discharges are . Answer: discharges that have intermittent,
dispersed flows having little or no control
◉The Texas Water Code establishes the protection