Water Treatment & Distribution Flashcards
What are the main causes of “red” water complaints?
Iron and Manganese
According to the Safe Drinking Water Act (SDWA), what are primary standards?
Primary standards relate to concerns that can cause immediate harm.
According to the Safe Drinking Water Act (SDWA), what are secondary standards?
Secondary standards are aesthetic concerns, such as taste and smell.
What is turbidity?
Turbidity is clay, silt, or mud in the water and relates to the clarity of the water. Turbidity should not be present in groundwater supplies.
What is the main cause of odor and taste complaints in surface supplies?
Algae
What is the main cause of odor and taste complaints in groundwater supplies?
Inorganic chemicals
What is the main cause of a “rotten egg” odor?
Hydrogen Sulfide (H2S)
What is pH?
pH is the measurement of the acidity of water using the concentration of hydrogen and hydroxide ions.
What is the Safe Drinking Water Act (SDWA)?
The Safe Drinking Water Act (SDWA) was passed in 1976. The law regulations include permissible Maximum Contaminant Levels (MCLs) for inorganic and organic chemicals, radioactivity, turbidity, and microbiological levels.
How is the Safe Drinking Water Act (SDWA) enforced throughout the country?
A primary agency in each state (like the ADEQ in Arizona) enforces the act. Their regulations include all of the SDWA regulations and can also include additional state-specific regulations.
Which of the following pH values is acidic?
A. 10.9
B. 8.2
C. 7.0
D. 4.5
D. 4.5
Water with a pH of 7.0 is:
A. Neutral
B. Alkaline
C. Acidic
D. Aerobic
A. Neutral
Chemical adsorption is used to remove:
A. Minerals
B. Organic materials
C. Bacteria
D. Turbidity
B. Organic materials
The chemical used in a gas stripping process is:
A. Oxygen
B. Chlorine
C. Iron
D. Ozone
A. Oxygen
What defines a Public Water System?
A public water system is defined as a system that has at least 15 service connections or regularly serves an average of at least 25 individuals daily at least 60 days out of the year.
Primary contaminants can be grouped into what 4 major categories?
Inorganic contaminants
Organic contaminants
Radiological contaminants
Microbiological contaminants
What is a “Maximum Contaminant Level” (MCL)?
The Maximum Contaminant Level (MCL) is the maximum amount of a substance that can be allowed in water, according to the regulations.
What do inorganic contaminants usually consist of?
Inorganic contaminants usually consist of heavy metals such as arsenic, copper, lead, and asbestos.
What is the Maximum Contaminant Level (MCL) for arsenic?
0.010 mg/L
When referring to the Lead and Copper Rule, what is a “first draw” sample?
A “first draw” sample is a sample taken from the customer’s tap after the water has been standing in the plumbing for at least 6 hours but no longer than 18 hours.
What is “Blue Baby Syndrome”?
A condition that occurs in pregnant mothers and infants under 18 months in which the presence of nitrate in the bloodstream reduces oxygen uptake, giving the skin a blue tint. The medical term for this illness is methahemoglobinemia.
What is the optimum dosage for flouride?
0.8-1.2 mg/L, usually determined by the average ambient air temperature for the system.
How is turbidity measured?
Turbidity is measured in Nephelometric Turbidity Units (NTUs), using a device called a nephelometer or a turbidimeter.
What is the Maximum Contaminant Level regarding pH?
6.5-8.5 mg/L