Water Nuggets Practice Exam 2.0
54 Degrees Fahrenheit
A 50% solution of caustic soda will begin to crystallize if the temperature drops below? 32 Degrees Fahrenheit 82 Degrees Fahrenheit 54 Degrees Fahrenheit 44 Degrees Fahrenheit
Destratification and Hypolimnetic Reaeration
A method to increase or maintain the DO concentration of a thermally stratified reservoir? Adding Copper Sulfate Destratification and Hypolimnetic Reaeration Adding Bluestone Adding Alum
<2.0 mg/L
A public water system that can not meet the required removal of TOC can comply if the source water TOC level is what, calculated quarterly as a running annual average. <1.0 mg/L <1.2 mg/L <2.0 mg/L <2.8 mg/L
Lower the pH
Adding CO2 to water will? Raise the pH Lower the pH Will turn the water a reddish color No noticeable change
Carryover from the Sedimentation Basin
An increase in filter media head loss could be an indicator of? Carryover from the Sedimentation Basin Filter is Ripening Filter run is short Flux Capacitor is clogged
Shearing
Anionic polymers are used as filter aids to agglomerate small floc particles left in the sedimentation basin effluent and make them tougher to avoid? Drowning Hovering Shearing Changing pH
Yellow
At its endpoint, what color does the oxidant potassium permanganate turn? Red Pink Reddish-brown Yellow
Present in the Natural Environment
Coliform bacteria are always? Harmful to Human Health Harmful to Human and Animal Health Present in the Natural Environment Harmful Only to Children and the Elderly
Once every four years
Community water systems must check the natural radioactivity in their water supply at least? Once a day Once a month Once a year Once every four years
2,000 ppm
Even a low concentration of ammonia gas can be fatal to humans if it is at least? 1 ppm 500 ppm 1,000 ppm 2,000 ppm
80 mg/L
Floc is produced when there is a chemical reaction between the coagulant and alkalinity. If the alkalinity of raw water is too low the floc formation will be poor. Some form of alkalinity must be added if the amount that is naturally found in the water source is less than? 80 mg/L 100 mg/L 150 mg/L 200 mg/L
3-5%
Gravity filters should not use more than what percent of daily production for backwash? 10-15% 3-5% 90-99% 17-20%
Every Hour
How often should the fluoride feed system be checked? Every Hour Every 24hrs Every Week Every Month
Media Depth and Media Size
If a filter is operating at a normal flow rate, its ability to trap flocculated particles is suspension is a function of? Media Depth and Uniformity Coefficient Effective Size Multiplied by Uniformity Coefficient Media Depth and Media Size Effective Size Multiplied by Uniformity Coefficient Divided by the Media Size
Temporary close the raw water inlet from that stream and use only well water to meet the demand
If there is a notification of a HazMat spill of an unknown chemical into a stream that provides water to a water treatment plant, what would be the best action taken? Shutdown the water plant Add more Cl2 Temporary close the raw water inlet from that stream and use only well water to meet the demand Lower the pH of the raw water
The backwash rate is too low
If there is debris found in the filter bed after backwashing a filter this can indicate? The backwash rate is too low Too many THMs Low Ammonia The backwash rate is too high
800
In pounds, how much ammonia is contained in a 1 ton cylinder that is full? 800 1,000 1,500 2,000
Blue Fluorescence
In the MNO-MUG test the presence of E.coli is indicted by? Red or Pink Color Blue Fluorescence Meter Count Green Color
Iron
Ion exchange processes can typically be used for direct groundwater treatment as long as turbidity and what else have levels that are not excessive? Sodium Sulfate Carbon Dioxide Iron Calcium Carbonate
1.0 mg/L
Manganese is rarely found in surface waters above a concentration of? 1.0 mg/L 2.0 mg/L 3.0 mg/L 10.0 mg/L
Oxidation of ammonia to form nitrite and nitrate
Nitrification in the distribution system can best be described as? The warming and cooling of the water in the actual water mains Oxidation of ammonia to form nitrite and nitrate The basic condition of hydrogen ions in the water system The changing of cells in pathogens during the treatment process into the distribution system
Carbon
Organic chemistry is concerned with compounds containing what element? Iron Manganese Carbon Sulfur
6 feet
Plant growth in a reservoir will usually be found at a depth of? 1 foot 6 feet 12-22 feet 40+ feet
Keep Iron Soluble in Water
Potassium permanganate and manganese greensand are sometimes used to? Increase the pH of raw water Coat pipes with film to prevent corrosion Never used together Keep Iron Soluble in Water
True
Protozoa are larger than bacteria which are larger than viruses. True False
Daily
Regulations require that wastes from water treatment be monitored? Daily Weekly Monthly Annually
True
Shellfish grown in polluted waters have been known to contain the organism that causes infectious hepatitis. True False
A Yellow Water Color
The Colilert test (ONPG-MUG) shows the presence of total coliforms is shown by? A Red/Pink Water Color A Yellow Water Color A Green Water Color A Blue Water Color
The removal, deactivation or killing of pathogenic microorganisms
The disinfection treatment process is? The sterilization of pathogenic organisms The removal, deactivation or killing of pathogenic microorganisms The removal of THM's and TDS from the finished water The removal or sterilization of drinking water from harmful viruses and bacteria
158-165 Degrees Fahrenheit
The fusible metal plugs on chlorine containers are designed to melt at what temperatures? 129-144 Degrees Fahrenheit 158-165 Degrees Fahrenheit 265-321 Degrees Fahrenheit 350-400 Degrees Fahrenheit
Calcium
The injection of fluoride should be as far away as possible from any chemical containing? Calcium Aluminum from Alum Chlorine Soda Ash
Nitrification and an increase in heterotrophic bacteria levels
The loss of chloramine residuals in a water line or a storage tank is due to? Not enough ammonia usage The DO levels are too low Nitrification and an increase in heterotrophic bacteria levels Hardness of water is too high
The more acidic the solution
The more hydrogen ions The more basic the solution The more acidic the solution The more more hydroactive The more radioactive the solution
The more basic the solution
The more hydroxide ions The more basic the solution The more acidic the solution The more more hydroactive The more radioactive the solution
Amperometric Titration
The most accurate chlorine residual measurement would be taken with? DPD pH Meter Jar Test Amperometric Titration
12" from the floor
The outlet of a forced ventilation system for a chlorinator room she be located? 12" from the floor 12' from the floor 2" from the floor 2' from the floor
100 mg/L Cl2
To regenerate virgin greensand it must be soaked in the filter bed for several hours in a solution of chlorine containing? 100 mg/L Cl2 200 mg/L Cl 2250 mg/L Cl2 300 mg/L Cl2
Bacteria
Waterborne diseases like typhoid and cholera are caused by? Viruses E.Coli Bacteria Cryptosporidium
3
What TON will consumers start to notice? 1 2 3 36
Use the Maximum Flocculator Paddle Speed Setting
What adjustments will the operator of a surface water treatment plant have to make if the raw water is very high in turbidity levels? Increase chemical feed pump Decrease chemical feed pump Use the Maximum Flocculator Paddle Speed Setting Use the Minimum Flocculator Paddle Speed Setting
More Dense Floc
What advantage over Aluminum Sulfate does Ferric Sulfate have? Cheaper to Use More Dense Floc Not Corrosive Less Dense Floc
HOCI & OCI-
What are the chemical symbols for hypochlorous acid and hypochlorite ions? H20 & HCI HCI & HOCI HOCI & OCI-
10.00 mg/L
What are total dissolved minerals in rainwater typically close to? 10.00 mg/L 48.00 mg/L 40.00 mg/L 1.00 mg/L
Shorter Filter Runs
What can immediately occur if newly installed manganese greensand was not skimmed of the fines after backwashing and stratification steps were completed? Mudball Formation Shorter Filter Runs Cracks Would Develop in the Bed Uneven Flow Through the Bed
All of the above
What changes does an operator need to make when there are issues with floc formation? Adjust Coagulant Dosage Change Coagulant Type Adjust Flocculator Mixing Intensity All of the above
Peroxone
What chemical oxidant is most effective in reducing the concentration of taste and odor compounds caused by actinomycetes species? Potassium Permanganate Chloride Dioxide Peroxone Chloramines
None of the above
What color will the water sample change when using amperometric titrator to check the chlorine residual? Pink Red Purple None of the above
Longer filter runs and a greater filtration rate
What conditions in a gravity filter will be produced when there is a larger particle size and less dense anthracite media? Longer filter runs and a reduced filtration rate Reduced filter runs and a reduced filtration rate Longer filter runs and a greater filtration rate None of the above
Total Trihalomethanes
What does a high pH favor the formation of? Both Haloacetic Acids and Total Trihalomethanes Neither Haloacetic Acids and Total Trihalomethanes Total Trihalomethanes Haloacetic Acids
Rotameter
What does the operator use to adjust the amount of liquid or gas delivered to water? Pump Rotameter Needle Valve Pinch Valve
An increase in the time required for coagulation
What effect will an increase in total dissolved solids in water to be treated be? An increase in the time required for coagulation An increase in Methane A decrease in pH In increase in free chlorine residual
Lead Gasket
What gasket is the best to use when connecting a chlorine cylinder or container to the chlorine feed system? Rubber Gasket Fiber Gasket Lead Gasket The original gasket must not be replaced
Nanofiltration
What is a similar process to reverse osmosis that uses lower pressures without removing all mineral content? Ninafiltration Ninofiltratin Nitrification Nanofiltration
Removing Iron
What is potassium permanganate most effective in? Removing Color Removing THMs Removing Iron Removing Chlorine
250 mg/L
What is the MCLG for chloride? 250 mg/L 142 mg/L 45 ppm 0 mg/L
The addition of an acid to lower pH before coagulation
What is the best addition for water that is highly colored due to organic matter? A small increase of nonionic polymer Increase of lime and the coagulant being used The addition of an acid to lower pH before coagulation The addition of lime
Polyphosphates and Chlorine
What is the best process for sequestering manganese? Polyphosphates Alone Polyphosphates and Chlorine Sodium Sodium Silicate
50 degrees
What is the minimum angle that self cleaning tube settlers must be placed? 10 degrees 45 degrees 50 degrees 90 degrees
Raw Water Intake
What is the most advantageous application point for powdered activated carbon? After Coagulation In the Filters Raw Water Intake After Oxidation with Chlorine
Granular Activated Carbon
What is the most effective method for removing tastes and odors? Granular Activated Carbon Coagulation, Sedimentation, and Filtration Lime Softening Anion Exchange
Anion Exchange
What is the most efficient process for the removal of nitrate and nitrate? Cation Exchange Anion Exchange Powered Activated Carbon Granular Activated Carbon
Use a disinfectant that targets the specific organisms in question
What is the most probable solution if crustaceans have clogged the water treatment plant's filters? Shutdown one filter at a time and drain Backwash filters using high concentration of ozone Use a disinfectant that targets the specific organisms in question Shutdown the filters and physically removed them
Disinfection By Product Rule
What is the rule that sets MCL's for harmful chemicals? Disinfection By Product Rule Safe Drinking Water Act Surface Treatment Water Rule O'doyle Rules
30 mins
What is the usual detention time required to produce optimal floc aggregation? 30 seconds 30 mins 30 hours 30 days
All of the above
What is true about heterotrophic bacteria? Heterotrophic bacteria are non-coliform growths which may suppress growth of coliform bacteria The organisms utilize organic carbon as a food source Heterotrophic bacteria are enumerated by a heterotrophic plate count at the end of 48hrs All of the above
Chloramines will form before the breakpoint and less Cl2 will be needed to reach breakpoint
What occurs in raw water as the level of ammonia decreases? Nothing Measurable THMs fall to 0 The DPD will turn red Chloramines will form before the breakpoint and less Cl2 will be needed to reach breakpoint
Cryptosporidium
What organism can escape coagulation and then pass through a granular filter? Cryptosporidium Giardia Naegleria Entamoeba
Iron and Manganese
What precipitates can foul a cation exchange resin? Iron and Manganese Sulfates Chlorate and Borate Sodium Chloride and Potassium Chloride
Chlorides, Nitrates, and DO
What should the an above ground raw water source be tested for if a water plant gets its water from a river that is subject to a cattle feed lot where water runs off? pH, Iron and DO Sulfates, Sulfuric Acid, and HAA5s Chlorides, Nitrates, and DO Chromium 6 and Manganese
Compound-loop control gas feeder
What type of chlorine gas feeding equipment would be most appropriate for distribution systems where re-chlorination is required? Chlorinator Stabilizer Venturi Compound-loop control gas feeder
All Hardness
What will ion exchange remove? Hardness down to 7.4 mg/L as CaCO3 Hardness down to 2.4 mg/L as CaCO3 Hardness down to 9.3 mg/L as CaCO3 All Hardness
In could inhibit floc formation
What will occur if the activation process of silica is not carefully controlled? In could inhibit floc formation The silica could splash due to high heat of reactants It could deposit silica on the flocculators and the gears It could corrode and destroy the metal and rubber in the flocculators
Polyphosphates
What would be best to use for corrosion inhibition if the water is very low in alkalinity and calcium concentration? Chlorine Chloramines Sodium Hydroxide Polyphosphates
Water Hardness and Langlier Index
What would have the least impact on the efficiency of copper sulfate? pH Alkalinity Water Hardness and Langlier Index Water Temperature
12 to 24hrs with 50 mg/L
When disinfecting a well with free chlorine, what is the required exposure time and what must the concentration be? 1 to 2 mins with 50 mg/L 1 to 2 hrs with 100 mg/L 6 to 8 hrs with 25 mg/L 12 to 24hrs with 50 mg/L
Floc Breakthrough
When filter run times between backwashes are long, like one week, because low turbidity water is being applied to the filters, what problem could still arise? Air Binding and Formation of Mudballs Air Binding Floc Breakthrough Mudball Formation
To ensure turbidity levels are less than 0.3 NTU
When treating surface water, the main reason for removing solids is? To ensure turbidity levels are less than 0.3 NTU Lower Cl2 Usage Increase DO Keep a stabilized pH
25 mg/L
When using the lime soda ash process, it is impossible to produce water with a hardness of less than? 50 mg/L 25 mg/L 100 mg/L 105 mg/L
MTF Method
Which is the method for testing for total coliform bacteria? ABC Method B&G Method MTF Method All of the above
Cryptosporidiosis
Which of the following illnesses is it hardest to kill the organism that causes the illness? Infectious Hepatitis Cryptosporidiosis Cholera Typhoid
Sedimentation is not as good in the summer months because the flows are higher and more floc is imbedded onto the filters
Why do mud balls and hard spots develop in high rate gravity filters during the summer months? The heat makes the water too had and then gets sticky The flow is too low because of lack of raw water The water becomes too hard and effects the filters Sedimentation is not as good in the summer months because the flows are higher and more floc is imbedded onto the filters
