The biggest drawback to UV disinfection is
leaves no residual
This is the measurement of the negative log of Hydrogen ions in a solution
pH
Centrifugal, positive displacement and turbine are all types of these
pumps
The ability of a liquid to resist a change in pH
Alkalinity
this type of fire extinguisher is for electrical equipment
Class C
this is known as 99.99% deactivation of waterborne pathogens
4-log disinfection
Chlorine that is remaining once the chlorine demand has been satisfied
residual
this positive displacement pump contains a flexible tubing to move liquids by pinching them through various rollers
peristaltic pump
Primarily made up of calcium and magnesium
Hardness
This can be used to find small chlorine gas leaks
ammonia
this can be used to remove taste and odor in drinking water
activated carbon
Turbidity is measured in these units
NTU's or nephelometric tubidity units
this is also known as the "heart" of a pump
impeller
surface water that is low in organics or productivity
oligotrophic
This substance is 2.5 times heavier than air
Chlorine gas
This form of chlorine is most effective at disinfection
Hypochlorous acid
Taste and odors in water are measured by this
Threshold odor number
SCADA
Supervisory control and data acquisition
the tendency for lakes to form distinct thermal layers
stratification
This is the minimum concentration in which most people can smell chlorine
0.3ppm
This conventional treatment step is eliminated by direct filtration
sedimentation
This chemical is used to neutralize chlorine when taking bacteria samples
Sodium thiosulfate
his type of pump cannot operate for very long with the downstream shut-off valve closed
positive displacement pumps
this process moves water into the air through plants and trees
transpiration
Records of chemical analysis must be retained by your public water system for this duration
10 years