system components
Head is measured in this unit
feet
the point at which the chlorine dosage has satisfied the chlorine demand
Breakpoint chlorination
a mechanical device consisting of 2 independently operating, spring loaded check valves with a reduced pressure zone between the 2 check valves
RPZ
a series of samples taken at different times from the sampling point and mixed together
Composite sample
A positive fecal coliform must be reported within
24 hours
water mains should primarily be sized primarily on this
fire flow and adequate pressures
booster chlorination should be added here
somewhere in the distribution system
a condition that can occur when pumps are run too fast or water is forced to change direction quickly
Cavitation
A collected sample that is accurately reflects the composition of water quality to be tested
Representative sample
The number of monthly distribution bacteria samples required is based on
population served
The measurement of a pipe's smoothness is known as this.
C-factor
The minimum required chlorine residual anywhere in the distribution system.
0.2 mg/L
a basic electrical unit that is used to measure a material's opposition to flow
Ohms
the water treatment process that kills disease-causing organisms in water, usually by the addition of chlorine
Disinfection
A system which fails to collect water samples in their distribution system would fall under which tier of public notification requirement
Tier 1
Protective methods for backflow-prevention devices in order of decreasing effectiveness are
Air gap, Reduced pressure zone, dual check valve assembly and vacuum breaker
Positive displacement meters typically do this when they are excessively worn
under-register
This type of valve can be used to to isolate a pump on the suction side.
Gate valve
This measurement for free chlorine residual is generally the simplest and quickest
DPD colorimetric method
the MCL for trihalomethanes
0.080 mg/L
This is the amount of liquid that can be raised vertically by a given pressure
Pressure head
This organism has the greatest resistance to chlorine
Giardia cysts
A rotating set of vanes that forces water through a pump
impeller
This chemical must be present to preserve a water sample when testing for total coliform
sodium thiosulfate
The surface water treatment rule requires disinfection residuals to be taken as the same time as these
coliform samples