T2 Practice exams
What is the maximum contaminant level goal for chloride?
250 mg/L
How much does a 1 ton chlorine cylinder weigh when it is full?
3,700 lb
Which is the maximum residual disinfection level goal for chlorine?
4 mg/L
A water supplier must report the failure to comply with any national primary drinking water regulation, including monitoring requirements, to the state primacy agency within _____ hours of occurrence.
48 hours
At what pH does the highest level of hypochlorous acid occur?
5
The flexible copper tubing that connects a 150-lb chlorine cylinder to a manifold should be rated at
500 psi
What is a normal groundwater pH level?
6.0 to 8.5
Samples collected for total coliform testing can be refrigerated for up to __ hours before analysis, but should be analyzed as soon as possible.
8 hours
What percent of the total chlorine residual is free chlorine beyond the chlorination breakpoint?
85 to 90%
The pH range of sodium hypochlorite is:
9.0 to 11.0 pH units
Manganese greensand filters can be regenerated by using:
A potassium permanganate solution for backwashing
According to the Surface Water Treatment Rule, how often must a system serving more than 500 people sample their filtered water for turbidity?
Every 4 hours
Methemoglobinemia (blue baby syndrome) is caused by an excessive concentration of which contaminant?
Excessive nitrate
Which fluoride compound comes in liquid form?
Fluorosilicic acid comes to the treatment facility as a liquid Sodium fluoride and Sodium fluorosilicate are in powder form
Which membrane process has been used for water softening and DBP precursor removal?
Nanofiltration
Tier 3 Violation
Requires the public water system to notify its customers within 12 months of learning of the violation. This may be accomplished by including the violation in the Consumer Confidence Report
Tier 2 Violation
Requires the water system to notify its customers as soon as possible, but within 30 days of learning of the violation and continue quarterly notifications as long as the violation persists
A backwash rate that is too high can cause gravel displacement which can lead to:
Sand boil
What type of breathing protection should be worn when handling chlorine leaks?
Self-contained breathing apparatus
What is the most likely result of high winds on a sedimentation basin?
Short-circuiting
Potassium permanganate:
Should be fed before chlorine
What type of PAC feed system should a plant that plans to only feed powdered activated carbon periodically install?
Slurry feed system
What chemical is used to remove residual chlorine from a bacteriological sample?
Sodium thiosulfate - Na2S203
Which commonly used base material produces an activated carbon with the smallest pore size of those listed?
The activated carbon produced with coconut shell has a smaller pore structure
If a groundwater system detects any organic compound in the chloroethylene family it will be required to monitor for _________ on a quarterly basis.
Vinyl chloride
How often should greased bearings be lubricated when in full service?
every 3 to 6 months
Excess lead and copper at the customer's tap caused by unstable water comes from:
household plumbing
Acids, bases, and salts lacking the element carbon are _________
inorganic compounds
Ion exchange softening processes can be used for direct groundwater treatment as long as turbidity and ________ are not too high.
iron levels
What is the removal rate of Cryptosporidium cysts in conventional sedimentation?
less than 0.5-log
What charge do suspended and colloidal solids have in natural water?
negative
A Stabilization process (recarbonation) is required following the lime softening process to prevent CaCO3 from precipitating out:
on the filters
Which analytical test can be performed by any person acceptable to the State?
pH Alkalinity Turbidity Calcium Conductivity Disinfectant Residual Orthophosphate Silica Temperature
Infectious hepatitis is caused by a type of:
virus
Why is air added during the reverse flow process of a microfiltration plant?
To improve the removal of fouling material
What is it called when water moves from leaves, grasses, and other plants to the atmosphere?
Transpiration
Because certain organisms are difficult to routinely test for, the EPA has designated ____________ ____________ as a means to maintain compliance.
Treatment techniques
The buildup of corrosion products on the inside of iron pipes is known as:
Tuberculation Its also the formation of "knobs" of rust on the interior of cast iron pipes
All suspended matter in water is called?
Turbidity
Who certifies water treatment plant laboratories for the measurement of total coliforms, fecal coliforms, and heterotrophic plate counts?
USEPA or the State
For water systems using conventional treatment or direct filtration, the turbidity level of representative samples of a system's filtered water must be less than or equal to ____
0.3 NTU in at least 95% of the samples collected each month
How many zones are there in a conventional sedimentation basin?
1 Influent zone 2 Settling zone 3 Effluent zone 4 Sludge zone
How many samples can be coliform positive if a water system collects less than 40 samples per month and the system still remain in compliance with the maximum contaminant level for Total Coliforms?
1 sample
How large must the sample be for lead and copper analyses?
1,000 mL or (1 liter)
What percentage of water produced by a conventional rapid sand filter is used for backwashing?
2 to 4%
The most common solution feeder used for liquid coagulants and coagulant aids is the
Metering pump
________ is commonly called swamp gas
Methane
Which membrane process is most comparable to a conventional gravity sand filter?
Microfiltration
A follow-up sample is required if the concentration in the composite sample is greater than or equal to ________ mg/L for any contaminant listed in the National Primary Drinking Water Regulations
0.0005 mg/L
The approximate surface area of 1 pound of GAC is:
150 acres of surface area
Samples to be analyzed for total coliforms by the total coliform Fermentation Technique, must be kept below _____
10 degrees Celsius during transit
Auxiliary equipment used for the fluoridation process includes:
A flow meter used for flow pacing (automatic chemical feed adjustment)
Following the lime softening process, how is the water stabilized?
Addition of carbon dioxide
What is it called when water moves through the air?
Advection
Addition of lime, caustic soda, or sodium bicarbonate may be required to aid the coagulation and flocculation of waters low in:
Alkalinity
What term describes the capacity of water to neutralize a strong acid?
Alkalinity is the capacity of water to neutralize a strong acid
One turn open on a chlorine cylinder will:
Allow maximum flow
Recreational activities near a reservoir can:
Alter the terrain or reduce the amount of native vegetation This can lead to erosion during rainfall
Self-contained breathing apparatus (SCBA) units:
Are fitted with a low-air-pressure alarm that alerts the wearer to leave the contaminated site
A community water system is defined as a water system with:
At least 15 service connections or serves at least 25 individuals daily for at least 60 days per year
Under no circumstances should a composite sample be collected for ____________
Bacteriological analysis
When/where is powdered activated carbon (PAC) usually added to the treatment process?
Before the coagulation-flocculation process
Manganese can cause a ______
Black stain on clothing and plumbing fixtures
Which are the two main elements that cause water hardness?
Calcium and magnesium
Hard water scale is usually caused by:
Calcium carbonate
What chemical is used to soften water by chemical precipitation of calcium and magnesium?
Calcium hydroxide (lime)
In addition to drinking water regulations, what regulation may govern the operation of a packed tower aeration system?
Clean Air Act due to their gas discharges
The minimum treatment required for a surface water system is to treat the water for:
Coliform bacteria and turbidity
What is used as an indicator of pathogens in a water supply?
Coliform group bacteria
Sodium fluoride
Comes in powder or crystal form, has no odor, and has pH of 7 when in a saturated solution.
What is considered to be "lead free" as it relates to solder and flux?
Containing not more than 0.02% lead
The residual chlorine test requires the use of what chemical?
DPD (diethyl-pheny-lene-diamine)
The Langelier Index of the raw and treated water should be calculated:
Daily
During the night, algae will cause the pH in a reservoir to:
Decrease
When ferric coagulants react with the natural alkalinity in the source water they form:
Diatomaceous earth filter
Killing or inactivation of pathogenic organisms in drinking water is called?
Disinfection
What does color in surface water indicate?
Dissolved organics may be present
Which device collects the settled water as it leaves the sedimentation basin?
Effluent launder
Two general classifications for the various membrane processes:
Electric driven and pressure driven
Chlorine storage rooms should:
Have a window to allow for visual inspection without entry
What zone of a reservoir will first become anaerobic?
Hypolimnion
The ________________ creates the vacuum that is required to operate the chlorinator
Injector
Which emergency kit is used for repairing a leak on a 1 ton chlorine container?
Kit B is used for 1-ton cylinders
What is the Best Available Technology (BAT) for removing radium-226 and radium-228 from source water?
Lime softening
Which material type is most likely to have water channels occur?
Limestone
Which statement is true regarding one-ton chlorine containers?
One-ton chlorine containers are equipped with two valves, one for liquid and one for gas
To permit maximum withdrawal rate when opening a chlorine cylinder valve:
Open only one turn
Powdered activated carbon is primarily used to remove or control:
Organic taste and odor causing compounds
Which aeration method is most commonly used for volatile organic chemical removal?
Packed Tower Aeration
Packing needs to be replaced when tightening does not stop leakage from the:
Packing gland
Which chemical oxidant/oxidation process is most effective in reducing taste and odor compounds caused by the actinomycetes species of bacteria?
Peroxone
In a microfiltration facility, which membrane material is most resistant to strong oxidants and acids?
Polyvinylidene fluoride (PVDF)
Tier 1 Violation
Poses immediate risk to public health and requires a clear notification to the public within 24 hours of learning of the violation
_____________________ should be fed as early as possible in the treatment process to allow complete reaction before it enters the distribution system
Potassium permanganate
What type of well is most commonly used around lakes and rivers?
Radial wells
What is the function of sodium thiosulfate in the coliform sample bottle?
Remove chlorine residual prior to analysis
When is it permissible for a water supplier to not report analytical results to the state?
When a state run laboratory performs the analyses
If ammonia vapor combines with chlorine gas leaking from a cylinder, what will appear?
White cloud
The turbidity leaving a slow sand filter must be:
≤ 1.0 NTU in 95% of the measurements collected each month
What are the turbidity requirements for diatomaceous earth filtration?
≤1.0 NTU in 95% of the measurements collected each month