T2 Prac 4 Flashcards
What is an example of a non-community, transient water system?
Rest stop
What might occur after a filter has been backwashed?
Turbidity momentarily increases in the filter effluent
What is the lowest reportable concentration for constituents called?
Detection level for reporting
What are part of the Multiple Tube Fermentation analysis?
Presumptive, Confirmed, Completed
What is a log 4 removal?
99.99%
What is considered to be a base?
pH range of 8 to 14
Which organisms use organic matter for energy and growth?
Heterotrophic
What organism is capable of causing diseases?
Pathogen
What is the term used to describe the removal or destruction of all microorganisms?
Sterilization
Which process releases water vapor into the atmosphere by living plants?
Transpiration
What is the zone of saturation?
The soil located below the top of the groundwater table
What is an example of combined chlorine?
Monochloramine
Which is a chlorine spill kit for a one-ton container?
Spill kit B
What is the purpose of pre-chlorination?
To control taste
What should be used to convey chlorine gas out of a one-ton container?
Upper valve
What is typically the cause of taste and odor problems in raw surface water?
Algae growth
What is the best pH for coagulation?
5-7
What are the 4 zones of a clarifier?
Inlet, outlet, settling, sludge
What is used to protect the underdrain in a filtration system?
Gravel
What is not a cause of a short filter run?
Low flow
What would not trigger a backwash in a filtration system?
Temperature
What is a breakthrough?
A crack in the filter bed that allows flocs to pass through
Where should sodium hypochlorite be stored?
Away from anything that will corrode
What is the Langlier’s Saturation Index?
An indicator of the corrosivity of water
What is the most resistant to a chemical disinfection?
Giardia cyst
What DBP would you expect to see in the water that is disinfected with ozonation?
Bromate
How long does it take to detect E. Coli using the Colilert method?
24 hours
Which chemical is used to remove turbidity?
Alum
What is the main purpose of the Surface Water Treatment Rule?
Removal of pathogens
Which layer of a stratified reservoir will most likely suffer from algae growth?
Epilmnion
What are very small particles that do not dissolve?
Colloids
What is a typical source of lead and copper in drinking water?
Corrosion of service pipe
What is an accurate lab equipment measuring device?
Pipet
What is the definition of operating ratio?
Ratio of annual operating expenses to operating revenue
What are the monthly sampling requirements based on?
Population served
Which constituent causes hard water?
Magnesium
When does chlorine and water reach breakpoint chlorination?
When it stops reacting with organics and inorganics
What is the problem with soft water?
Corrosion
What’s considered soft water?
Less than 60 mg/l CaCO³
What would not be used to treat hard water?
Carbon dioxide
What’s another name for caustic soda?
Sodium hydroxide
If a significant amount of iron is present in water, what are the adverse impacts?
Taste and staining
What is the health impact of drinking water with excess lead?
Development problems in children
What is the impact of TDS on water?
Bad taste
Which of the technologies is the most effective way to remove TDS?
Reverse Osmosis
What is an organic precursor?
Humic acid
What is the impact of overdosing potassium permanganate in water?
Pink water
Where are samples for lead and copper typically obtained?
Consumer’s tap
What is the most common way to test for E. Coli?
Colilert
What is the best way to minimize THMs?
Don’t prechlorinate
When must the public be notified of a Tier 1 violation regarding their water supply?
Within 24 hours after the occurrence of violation
What is titration?
A process of adding the chemical reagent in small increments until completion of reaction
What is supernatant?
The relatively clear water layer between the sludge on the bottom and the scum on the surface of a basin
Which would contribute to alkalinity? Calcium, bicarbonate, sodium or potassium
Bicarbonate
What’s regulated under the Secondary Drinking Water Standards?
Odor
What’s a requirement for viruses under the Surface Water Treatment Rule?
99.99% removal and/or inactivation
What is the process that transfers water vapor from living plants into the atmosphere?
Evapotranspiration
When must a repeat sample be taken?
Sample tests positive for total coliform
Why is fluoride injected into drinking water?
Reduce tooth decay
What would be used to test chlorine residual in the field?
DPD
What is the largest zone in a sedimentation tank?
Settling zone
What would describe the attributes of chlorine dioxide?
It does not form carcinogenic compunds
What is the common source of coliform?
Feces
What is the hypogeal biological layer formed on the surface of a slow sand filter?
Schmutzdecke
What would lead to thermal stratification?
When surface water begin to warm
What’s true about using an inclined plate settler?
Uses a smaller footprint at the plant than a conventional clarifier
What would most likely lead to nitrification?
High concentration of ammonia in water
What is the probable cause of reddish brown water?
Iron
What constituent makes water turn black?
Manganese
What is a potentially dangerous condition in a confined space?
Oxygen content drops below 19.5% by volume
What’s not true about tuberculation?
Increases pipe capacity
What is the secondary MCL?
Sets limits for constituents that affect the aesthetic qualities of drinking water
What is a tier 1 violation?
Exceeding MCL for nitrate
What is used to control the injection of gas chlorine into water?
Chlorinator
What is a venturi-style injector used for chlorine gas?
Eductor
What would happen if a valve is closed too quickly?
Water hammer
When must a public notice be issued to the customer?
When there is a serious problem with the drinking water
What would cause manganese to precipitate?
Adding sodium hypochlorite
What is the purpose of Total Coliform Rule?
Improve public health protection by reducing fecal pathogens to minimal levels
What type of pump is used as a chemical metering pump?
Positive displacement pump
If you have rights to pull water out of an adjacent river due to the purchase of land, which rights do you have?
Riparian
What’s a typical characteristic of surface water?
Higher turbidity and organics
If groundwater near an ocean has high concentration pf chloride, what may be true?
Seawater intrusion is occuring
What is the thermocline?
Metalimnion
What is the purpose of a sanitary seal in a well?
Prevent contamination of groundwater supply
