Wastewater License Exam
the mechanism used to remove dewatered sludge from the belt of a belt filter press is
commonly referred to as a: - correct answer-doctor blade
over a period of time, ultraviolet lights lose their intensity and must be replaced (T?F) -
correct answer-TRUE
Which of the following statements is true regarding ultraviolet light disinfection systems? -
correct answer-regular cleaning of light tubes is necessary to maintain optimal performance.
uv light leaves no harmful residuals
The wastewater disinfection process is designed to: - correct answer-destroy (kill) the
pathogenic (disease causing) microorganisms in the wastewater. typically, this is the final
stage of treatment before the wastewater is discharged
pathogenic organisms are: - correct answer-are viewed as harmful, disease causing
microorganisms and are destroyed to prevent the spread of disease. pathogenic organisms
include bacteria, viruses, or cysts which can cause diseases such as typhoid, cholera, or
dysentery
emergency kit "a" is designed for use with: - correct answer-100 & 150 pound capacity
cylinders
in a conventional activated sludge plant....the principal purpose of returning sludge to the
aeration tank is... - correct answer-maintain a satisfactory biological population
the mean cell residence time is: - correct answer-an expression of the average time, in days,
that a microorganism will spend in the activated sludge process
the mechanism used to remove dewatered sludge from the belt of a belt filer process is
commonly referred to as a: - correct answer-doctor blade
during the dewatering process the water that is removed or separated from the centrifuge is
called - correct answer-centrate
the solubility of oxygen decreases as temperature - correct answer-increases
the temperature versus DO relationship is - correct answer-the lower the temperature then
the higher the DO
in an activated sludge plant, if the DO in the aeration tank suddenly decreases and the
aerators are not the problem...what is the most probable cause? - correct answer-increased
organic load
, in an activated sludge plant, if the DO in the aeration tank steadily increases and the
aerators are not the problem...what is the most probable cause? - correct answer-a toxic
industrial slug load
when nitrification occurs in an aeration tank, the expected conditions at the end of the
aerated zone would be: - correct answer-an increase in nitrate and nitrite, a decrease in
alkalinity and pH
nitrification is the biological oxidation of NH4+ to NO3- through a two-step process by the
bacteria _______ - correct answer-remus and romulus
ultraviolet disinfection is form of wastewater disinfection that operates on the principle that
radiation - correct answer-alters the DNA of a bacterial cell preventing the reproduction of
that cell
after performing maintenance on a postive-displacement pump, ensure that the following
task is performed before starting the pump - correct answer-the valve(s) on the discharge
side of the pump is (are) open
what chemical can be used to detect chlorine leaks? - correct answer-ammonia
an accident prevention program, in general, involves which of the following sets of steps? -
correct answer-recognition of hazards, evaluation of hazards, and control of hazards
what is the purpose of the (material) safety data sheet? - correct answer-to provide health
and safety information regarding the use and handling of materials
an "attached" growth biological process - correct answer-trickling filter and rotary biological
contactor (RBC)
a "suspended" growth biological process - correct answer-sequencing bioreactor (SBR) and
membrane bioreactor (MBR)
wastewater is distributed over rocks and trickles down to underdrains - correct
answer-trickling filter
large, partially submerged "discs" which rotate continuously, so that the microorganisms
growing on the disc's surface are repeatedly being exposed alternately to the wastewater
and to the air - correct answer-rotary biological contactor (RBC)
sulfuric (h2SO4) - correct answer-acid
sodium hydroxide (NaOD) - correct answer-base
sodium hypochlorite (NaOCl) - correct answer-oxidizer
what parameters define the efficiency of secondary treatment processes in removing
organics and suspended solids? - correct answer-BOD and total suspended solids
the mechanism used to remove dewatered sludge from the belt of a belt filter press is
commonly referred to as a: - correct answer-doctor blade
over a period of time, ultraviolet lights lose their intensity and must be replaced (T?F) -
correct answer-TRUE
Which of the following statements is true regarding ultraviolet light disinfection systems? -
correct answer-regular cleaning of light tubes is necessary to maintain optimal performance.
uv light leaves no harmful residuals
The wastewater disinfection process is designed to: - correct answer-destroy (kill) the
pathogenic (disease causing) microorganisms in the wastewater. typically, this is the final
stage of treatment before the wastewater is discharged
pathogenic organisms are: - correct answer-are viewed as harmful, disease causing
microorganisms and are destroyed to prevent the spread of disease. pathogenic organisms
include bacteria, viruses, or cysts which can cause diseases such as typhoid, cholera, or
dysentery
emergency kit "a" is designed for use with: - correct answer-100 & 150 pound capacity
cylinders
in a conventional activated sludge plant....the principal purpose of returning sludge to the
aeration tank is... - correct answer-maintain a satisfactory biological population
the mean cell residence time is: - correct answer-an expression of the average time, in days,
that a microorganism will spend in the activated sludge process
the mechanism used to remove dewatered sludge from the belt of a belt filer process is
commonly referred to as a: - correct answer-doctor blade
during the dewatering process the water that is removed or separated from the centrifuge is
called - correct answer-centrate
the solubility of oxygen decreases as temperature - correct answer-increases
the temperature versus DO relationship is - correct answer-the lower the temperature then
the higher the DO
in an activated sludge plant, if the DO in the aeration tank suddenly decreases and the
aerators are not the problem...what is the most probable cause? - correct answer-increased
organic load
, in an activated sludge plant, if the DO in the aeration tank steadily increases and the
aerators are not the problem...what is the most probable cause? - correct answer-a toxic
industrial slug load
when nitrification occurs in an aeration tank, the expected conditions at the end of the
aerated zone would be: - correct answer-an increase in nitrate and nitrite, a decrease in
alkalinity and pH
nitrification is the biological oxidation of NH4+ to NO3- through a two-step process by the
bacteria _______ - correct answer-remus and romulus
ultraviolet disinfection is form of wastewater disinfection that operates on the principle that
radiation - correct answer-alters the DNA of a bacterial cell preventing the reproduction of
that cell
after performing maintenance on a postive-displacement pump, ensure that the following
task is performed before starting the pump - correct answer-the valve(s) on the discharge
side of the pump is (are) open
what chemical can be used to detect chlorine leaks? - correct answer-ammonia
an accident prevention program, in general, involves which of the following sets of steps? -
correct answer-recognition of hazards, evaluation of hazards, and control of hazards
what is the purpose of the (material) safety data sheet? - correct answer-to provide health
and safety information regarding the use and handling of materials
an "attached" growth biological process - correct answer-trickling filter and rotary biological
contactor (RBC)
a "suspended" growth biological process - correct answer-sequencing bioreactor (SBR) and
membrane bioreactor (MBR)
wastewater is distributed over rocks and trickles down to underdrains - correct
answer-trickling filter
large, partially submerged "discs" which rotate continuously, so that the microorganisms
growing on the disc's surface are repeatedly being exposed alternately to the wastewater
and to the air - correct answer-rotary biological contactor (RBC)
sulfuric (h2SO4) - correct answer-acid
sodium hydroxide (NaOD) - correct answer-base
sodium hypochlorite (NaOCl) - correct answer-oxidizer
what parameters define the efficiency of secondary treatment processes in removing
organics and suspended solids? - correct answer-BOD and total suspended solids
