safe drinking water act
what is 1974
is set because of health concerns
is set because of aesthetic concerns
Primary
Secondary
This index is used to calculate corrosion where neg numbers mean corrosion and positive numbers mean scale building
Langelier saturation index pH(A)-pH(S)
At higher temperatures reactions are
faster
new pipes any anything that is being disinfected must have a _____ chlorine and must stay at ____ for __ hrs
50ppm, 25ppm, 24hrs
revision science-based evidence, consumer confidence, EPA standards certification
1996
blue baby syndrome is caused by exceeding the MCL of ?
nitrates
are corrosion inhibitor
Phosphates
what are some oxidation methods
aeration, Cl, potassium compounds, ozone
Causes of air binding
Dissolved oxygen, higher temp, high headloss
This is the causes the most health-related issues roughly 50%
cross connections or back flow
E.Coli has an MCL of?
any
This type of corrosion involves direct current though different metals
the way to prevent this type of corrosion is?
Galvanic
sacrificial anodes normally Zn or Mg
are the surface water characteristics that need to be monitored?
PH
Alkalinity
Temp
Turbidity
Hardness
Color
Taste odor
Organic compounds
Total volatile synthetic compounds
Dissolved Oxygen
Total dissolved solids
combines micro sand with floc particles to accomplish treatment more rapidly than conventional treatment
Actiflo
after June 30th an operator has how long to renew licence without a test
6 months
heterotrophic plates count measure?
all bacteria in the sample
The higher the DO the__________ the corrosion rate
higher
Chlorine is a yellow-green gas is what compared to air
2.5X heavier
non-uniform velocities of water flow
short-circuiting
this is when water treatment licenses need to be renewed
June 30th of even-numbered years
Floride recommended:
2nd MCL:
primary MCL:
0.7 mg/L
2mg/L
4mg/L
what is the optimum pH range for Alum
6-7
This is the strongest disinfectant available for potable water
Ozone
most efficient/economical way to improve settling
tube settlers