Advanced Treatment Process Flashcards by Eric Hurley

If clarification and filtration follow aeration, what process will most likely suffer most if too much aeration occurs?
a. Sedimentation problems
b. Coagulation
c. Filtration
d. Post-disinfection

a. Sedimentation problems

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Jar tests are used to determine the powdered activated carbon (PAC) dose. The glassware used in these jar tests need to be cleaned with __ ___ and rinsed with _ ____ water.
a. Phosphate-free detergent, deionized
b. Phosphate-free detergent, copious amounts of
c. Unscented detergent, odor-free
d. Unscented detergent, copious amounts of

a. Phosphate-free detergent, deionized

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The rate of formation of ___ __ increases with increasing pH.
a. HAA5
b. Nitrates
c. THMs
d. Organophosphates

d. Organophosphates

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In variable declining-rate filtration, what is placed in the effluent line of each filter to prevent excessive flow rates?
a. A rate-of-flow controller
b. A flow-restricting orifice plate
c. A variable solenoid-controlled butterfly valve
d. Pressure-controller valve

b. A flow-restricting orifice plate

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A tracer study uses a substance that can readily be identified in water to determine the __ ___ in a basin, pipe or channel.
a. Reaction time and flow pattern
b. Reaction time and distribution
c. Flow pattern and distribution
d. Distribution and detention time

d. Distribution and detention time

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Both, the amount and types of disinfection byproducts formed depend on the organic precursors present, but also on the _____.
a. Type of disinfectant used and the contact time with that disinfectant
b. Alkalinity
c. Temperature
d. Conductivity

a. Type of disinfectant used and the contact time with that disinfectant

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What is the best practice to follow for a filter that is air-bound?
a. Remove from service and backwash thoroughly
b. Close the effluent valve and fill the filter as high as permissible. The extra pressure on the media will force the air out slowly. This takes about 15 – 45 minutes for most filters. After bubbles stop rising from the filter for 5 minutes, the filter is ready to be put back into service
c. Simply bump the filter to release all the gasses. It may need to be bumped several times until bubbles stop being released
d. Both a and b

a. Remove from service and backwash thoroughly

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In manganese greensand filters, the greensand is usually capped with at least _____.
a. 6-in of anthracite
b. 6-in of coarse sand and 6-in of anthracite
c. 12-in of garnet
d. 6-in of coarse sand and 12-in of anthracite

a. 6-in of anthracite

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Lamella plates work by _____.
a. Using plates that are inclined by 40 ֯
b. First using plates that are directed downward by 20 ֯ and then upward into plates inclined by 45 ֯
c. Using plates directed downward at 45 ֯ then upward at 45 ֯
d. Using parallel plates that direct water downward then upward at 55 ֯

d. Using parallel plates that direct water downward then upward at 55 ֯

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The flow through a sedimentation basin should not exceed _____.
a. 0.5 ft/min
b. 0.8 ft/min
c. 1.0 ft/min
d. 1.5 ft/min

a. 0.5 ft/min

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What is the mechanism by which potassium permanganate works when used to control algae?
a. It disrupts the algae’s DNA, thus killing it
b. It precipitates iron, which is needed by the algae for chlorophyll production
c. It reacts with the algae cell wall, causing it to lyse and thus die
d. It disrupts the algae’s mitochondria, thus killing it

b. It precipitates iron, which is needed by the algae for chlorophyll production

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If THMs are still a problem after softening, and changing the disinfectant is not an option, what other treatment processes can be used and what is its disadvantage?
a. Granular Activated Carbon (GAC), rather expensive
b. Powdered Activated Carbon (PAC), high maintenance
c. Tube settlers, difficult to clean
d. Coagulant aid, additional maintenance

a. Granular Activated Carbon (GAC), rather expensive

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What process is currently used for softening brackish water?
a. Nanofiltration
b. Electrodialysis
c. Freezing
d. Lime – soda ash process

a. Nanofiltration

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Greensand filters are often capped to enhance filter performance and improve backwash efficiency. It is common to cap them with _____.
a. 1 – 2 in of granular activated carbon (GAC)
b. 12-in of GAC
c. 6-in of anthracite
d. 18-in of anthracite

d. 18-in of anthracite

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What other effect does aeration have besides oxidizing iron and manganese?
a. It removes organics via reduction
b. It removes CO2, which enhances oxidation because it raises the pH
c. It inactivates Cryptosporidium, including their oocysts
d. It destroys or inactivates all bacterial pathogens

b. It removes CO2, which enhances oxidation because it raises the pH

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Chloramines will be used when tastes and odors are a problem, particularly when the source water contains _____.
a. Humic acids
b. Phenols
c. Tannic acids
d. Capsaicin

b. Phenols

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That treatment chemical is corrosive, dense, and an oily liquid and available in strengths of 62%, 78%, and 93%?
a. Sodium hexametaphosphate
b. Zinc orthophosphate
c. Caustic soda
d. Sulfuric acid

d. Sulfuric acid

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Besides oxidizing iron and manganese, potassium permanganate has been found to be most effective in controlling _____.
a. Zebra mussels
b. Vibrio cholerae
c. Salmonella typhi
d. Protozoans

a. Zebra mussels

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Dissolved Air Flotation (DAF) has achieved a _____ removal of Cryptosporidium, which compares to a removal rate of less than 0.5-log using conventional sedimentation.
a. 1.0-log
b. 1.5-log
c. 2.0-log
d. 2.5-log

c. 2.0-log

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__ ___ will outperform _ ____ in open filters in the removal of organics.
a. Anthracite, GAC
b. GAC, anthracite
c. PAC, slow sand filters
d. PAC, GAC

b. GAC, anthracite

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Iron complexes with __ ___ are __ ___ in chemistry, and they are not removed by __ ___.
a. Sulfate, cationic, cation exchange
b. Sulfate, anionic, anion exchange
c. Organic matter, cationic, mixed bed resins
d. Organic matter, anionic, cation exchange

d. Organic matter, anionic, cation exchange

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A special problem with granular activated carbon (GAC) filters is the rapid growth of _____.
a. Helminths
b. Amoebas
c. Algae
d. Bacteria

d. Bacteria

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How is aluminum oxide activated?
a. Oxygen and heat
b. Sulfuric acid and heat
c. Heat and washing with sodium hydroxide
d. Carbon dioxide wash with HCL and heat

c. Heat and washing with sodium hydroxide

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What is the most common scale-forming precipitate?
a. MgCO3
b. MgCl2
c. CaCO3
d. CaSO4

c. CaCO3

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What membrane configurations are currently available and used in drinking water treatment plants? a. Spiral wound and hollow fiber b. Spiral wound and tubular fiber c. Tubular and hollow fiber d. Hollow fifer and plate & frame

a. Spiral wound and hollow fiber

26. The __ ___ and settling of calcium carbonate and magnesium hydroxide precipitates occur more __ ___ in the presence of _ ____. a. Flocculation, quickly, previously formed floc particles b. Softening reactions, quickly, calcium carbonate granules c. Coagulation, slowly, calcium carbonate granules d. Chemical reactions, quickly, too much sludge so frequent removal is necessary

a. Flocculation, quickly, previously formed floc particles

A low-cost method of feeding powdered activated carbon (PAC) is to use a _ ____, where precise feed is __ ___. a. Helix-type, primary b. Helix-type, secondary c. Slurry feed, primary d. Slurry feed, secondary

b. Helix-type, secondary

If powdered activated carbon (PAC) does not remove tastes and odors, it could be that it is added too close to the chlorine feed. To solve this problem, PAC should be added so that it has at least _ ____ of contact time before chlorine is added. a. 10 min b. 15 min c. 20 min d. 25 min

b. 15 min

To prevent serious loss of media, it is recommended that surface washers be turned off __ ___ minutes before the end of the main backwash. a. 1 – 2 b. 3 – 5 c. 4 – 7 d. 7 – 10

a. 1 – 2

30. The lime – soda ash process has the following characteristics: a. It softens the water at a moderate cost b. It can be used for both, groundwater and surface water c. It is most often used at small treatment plants d. All of the above

b. It can be used for both, groundwater and surface water

No preliminary contact or sedimentation chambers are necessary for _____. a. Aeration with oxygen b. Potassium permanganate oxidation c. Manganese greensand d. Ozone oxidation

d. Ozone oxidation

What is the percentage of copper in copper sulfate (CuSO4)? a. 39.80% Cu b. 39.81% Cu c. 39.84% Cu d. 39.88% Cu

a. 39.80% Cu

Diatomaceous earth filtration is used for raw water that has a maximum turbidity of _____. a. 5 ntu b. 10 ntu c. 20 ntu d. 40 ntu

b. 10 ntu

What two methods are commonly used for drinking water supplies to control algae at the source? a. Copper hydrate and activated carbon b. Potassium permanganate and anthracite c. Potassium sulfate and anthracite d. Copper sulfate and powdered activated carbon

d. Copper sulfate and powdered activated carbon

What could cause eddies in a clarifier or sedimentation basin? a. Uneven flow over the weir b. Broken baffle c. Sludge level too high d. Gusting winds

a. Uneven flow over the weir

What chemical used for oxidizing iron and manganese needs a reaction basin? a. Chlorine b. Chlorine dioxide c. Ozone d. Potassium permanganate

c. Ozone

What is produced after colloids have just become charge neutralized? a. Stabilized microfloc b. Stabilized colloid c. Macrofloc d. Agglomerated microfloc

d. Agglomerated microfloc

In a dual media filter, it is best to have _ ___ backwash rates because each type of media has a different __ ___. a. Two, particle size and thus surface area b. Two, specific gravity c. Three, particle size and thus surface area d. Three, specific gravity

b. Two, specific gravity

Reverse Osmosis (RO) units also have cartridge filters installed immediately ahead of the RO unit to remove suspended matter down to _____. a. 1 – 3 mm b. 3 – 5 mm c. 5 – 10 mm d. 10 – 15 mm

c. 5 – 10 mm

What chemical used for oxidizing iron and manganese will react with hydrogen sulfide, cyanides, phenols, and other taste and odor compounds, and will not form trihalomethanes? a. Chlorine dioxide b. Potassium permanganate c. Ozone d. Chlorine

b. Potassium permanganate

How does bentonite clay improve coagulation? a. Adds alkalinity b. Increases pH c. Makes the floc heavier d. Stabilizes the charge on the particle

c. Makes the floc heavier

A filter core sample is best collected for solids retention analysis _____. a. When the filter media is dry b. When the filter media has been drained and the media is still damp c. When the water has been drained to just above the media d. At any of the above scenarios

b. When the filter media has been drained and the media is still damp

If sludge removal scrapers are installed at a plant, it is not necessary to interrupt plant operations to take the basin out of service as frequently as basins without scrapers. However, the basins will need to be dewatered and hose-blasted at least _____. a. Monthly b. Once per year c. Every 2 years d. Every 3 years

b. Once per year

To maintain the optimum powdered activated carbon (PAC) dose, the threshold odor tests should be performed on the raw water and finished water while PAC is being fed at least _____. a. Daily b. Weekly c. Bimonthly d. Monthly

a. Daily

Engineers usually design the height of a filter’s backwash collection trough to allow for _ ____ bed expansion without loss of media into troughs. a. 25% b. 30% c. 40% d. 50%

d. 50%

What is the best way to save on chemical costs when softening hard water if the Surface Water Treatment Rule does not apply to the system? a. Reverse osmosis b. Enhanced coagulation c. Lime – soda ash d. Split treatment

d. Split treatment

Excess air from aeration will cause air to attach to floc, making the floc _ ____and not settle. It may also attach to the filter media, if the water __ ___ as it passes through the filter media, which, if it continues long enough, will cause __ ___. a. Disperse, warms, air binding b. Disperse, cools, clogging c. Float, warms, air binding d. Float, cools, clogging

c. Float, warms, air binding

The pores in carbon are created by exposing the carbon to __ ___. This process is known as __ ___ the carbon. a. Very high heat in the presence of steam, carbonizing b. High pressure steam, tunneling c. High pressure steam, cracking d. Very high heat in the presence of steam, activating

d. Very high heat in the presence of steam, activating

Dewatering of alum and ferric sludge is difficult because the water is _____. a. Covalently bonded to the hydroxide ions in the floc b. Covalently bonded to the aluminum or ferric cations in the floc c. Chemically bound to the aluminum and ferric hydroxide floc d. Physically bound to the aluminum and ferric cations

c. Chemically bound to the aluminum and ferric hydroxide floc

Regarding the two-stage recarbonation process, the raw water pH is elevated to _____ or greater with lime. After that stage, carbon dioxide is added to lower the pH to _____. a. 10, 9.0 – 9.5 b. 11, 10.0 – 10.6 c. 10, 9.5 – 9.9 d. 12, 10.4 – 10.7

b. 11, 10.0 – 10.6

What is the advantage that coagulants such as ferric sulfate have over alum? a. They are not as affected by temperature b. They work over a wider pH range c. They need very little alkalinity d. They are not affected by pre-chlorination

b. They work over a wider pH range

The __ ___ process is used in the water industry primarily for the removal of _ ____. a. Adsorption, organic substances b. Adsorption, inorganic substances c. Absorption, organic substances d. Absorption, inorganic substances

a. Adsorption, organic substances

Water that is highly colored with organic material requires a __ ___ pH for coagulation; therefore, ___ __ before __ ___ may be necessary. a. Lower, acid addition, flocculation b. Higher, alkalinity addition, flocculation c. Lower, acid addition, coagulation d. Higher, alkalinity addition, coagulation

c. Lower, acid addition, coagulation

__ ___ is often added to provide __ ___ and facilitate iron precipitation. a. Lime, alkalinity b. Soda ash, a higher pH c. Caustic, basicity d. Sodium bicarbonate, a higher pH

a. Lime, alkalinity

A hazardous measuring device would most likely be _____. a. A pressure-activated level transmitter b. A laser particle counter c. A nephelometric meter d. A manometer

d. A manometer

What acid is even more corrosive when diluted than when it is pure? a. Sulfuric acid b. Hydrochloric acid c. Nitric acid d. Phosphoric acid

a. Sulfuric acid

What gas(es) does electrolytic flotation use? a. Air b. Nitrogen c. Carbon dioxide d. Hydrogen and oxygen

d. Hydrogen and oxygen

Reverse osmosis membranes need cleaning if the pressure drop through the unit increases by __ ___. a. 10% b. 15% c. 20% d. 25%

c. 20%

What alum sludge dewatering process can attain at least 20% solids by weight? a. Drying lagoon b. Vacuum filters c. Sand drying beds d. Freezing and thawing method

b. Vacuum filters

__ ___ are used to regenerate ion-exchange systems and are also used to __ ___ the pH of water treated by nanofiltration and ___ __. a. Bases, raise, microfiltration b. Bases, raise, reverse osmosis membranes c. Acids, lower, reverse osmosis membranes d. Acids, lower, microfiltration

c. Acids, lower, reverse osmosis membranes

Water flowing through a full pipeline has a velocity of 1.75 ft/s. if the flow through the pipe is 0.35 ft3/s, what is the diameter in inches, of the pipeline? a. 3.0 in b. 4.0 in c. 5.0 in d. 6.0 in

d. 6.0 in

What is the velocity of flow in ft/s for an 8.0-in diameter pipe if it delivers 182 gpm? a. 0.9 ft/s b. 1.2 ft/s c. 3.6 ft/s d. 8.7 ft/s

b. 1.2 ft/s

The iron in a corroding pipe releases two electrons at the anode. What will these electrons combine with in the pipe? a. Metal cations in the flowing water at the cathode b. Organics in the flowing water c. Ferrous hydroxide at the cathode d. Two hydrogen (H+) ions to form hydrogen gas

d. Two hydrogen (H+) ions to form hydrogen gas

An organic contaminant from coagulants would most likely include ____. a. Epichlorohydrin b. Polynuclear aromatic hydrocarbons c. Polychlorinated biphenyls d. Tetrachloroethylene

a. Epichlorohydrin

What pH is needed to form the magnesium hydroxide precipitate? a. Above 9.0 b. Above 9.2 c. Above 9.5 d. Above 10.6

d. Above 10.6

Chlorite monitoring requirements include __ ___ sampling and analysis at the distribution system’s entry point and __ ___ sampling and analysis at locations in the distribution system. a. Daily, quarterly b. Daily, monthly c. Monthly, quarterly d. Monthly, monthly

b. Daily, monthly

In dual media, if the ratio of anthracite size to sand size is close to __ ___, a sharp interface will be created and __ ___ and possibly __ ___ will result. a. 2, too much intermixing, poorer quality filtrate b. 2, excessive head losses, mudball formation c. 4, excessive head losses, mudball formation d. 4, too much intermixing, poorer quality filtrate

b. 2, excessive head losses, mudball formation

What type of aerators have riffle plates? a. Cone aerators b. Salt-and-coke tray aerators c. Cascade aerators d. Spray aerators

c. Cascade aerators

Scale is formed from the combination of _____. a. Monovalent metallic ions with carbonates or sulfates b. Monovalent metallic cations and minerals dissolved in water c. Divalent metallic ions with carbonates or sulfates d. Divalent metallic cations with minerals dissolved in water

d. Divalent metallic cations with minerals dissolved in water

A plant uses a coagulant aid that weighs 10.05 lb/gal to help treat 10.8 mgd. The coagulant aid’s strength is 50%. The results of a drawdown test are 112 ml for the coagulant aid in 5 min. What is the coagulant aid dosage in ppb? a. 470 ppb of coagulant aid b. 475 ppb of coagulant aid c. 480 ppb of coagulant aid d. 485 ppb of coagulant aid

b. 475 ppb of coagulant aid

Water treatment plants that use powdered activated carbon consistently have found the handling problems are less by using _____. a. Dry gravimetric feeders b. Volumetric feeders c. Slurry feed system d. Helix-type feeders

c. Slurry feed system

A 0.5N solution of NaOH is to be prepared. If 1 L of solution is desired, how many grams of NaOH are required? The gram formula for NaOH is 40.00. a. 10 g of NaOH dissolved in 1 L of deionized water b. 20 g of NaOH dissolved in 1 L of deionized water c. 40 g of NaOH dissolved in 1 L of deionized water d. 80 g of NaOH dissolved in 1 L of deionized water

b. 20 g of NaOH dissolved in 1 L of deionized water

Alum sludge that has been dewatered in a lagoon for a year may still contain more than __ __ of the original water. a. 75% b. 80% c. 90% d. 95%

c. 90%

What membrane process will remove hardness? a. Nanofiltration and reverse osmosis b. Nanofiltration and ultrafiltration c. Ultrafiltration and microfiltration d. Reverse osmosis and ultrafiltration

a. Nanofiltration and reverse osmosis

What corrosion prevention chemical may actually cause tuberculation in iron pipes in the pH range of 7.5 – 9.0? a. Lime b. Phosphates c. Sodium bicarbonate d. Sodium hydroxide

d. Sodium hydroxide

The cleaning of microfiltration membranes helps maintain a stable __ ___ while keeping recovery at or above __ ___. a. Flux, 95% b. Flux, 99% c. Pressure feed, 95% d. High pressure feed, 99%

b. Flux, 99%

The fluoride injection point should be as far away as possible from any _____. a. Phosphate chemicals used for corrosion control b. Polymers used in coagulation c. Calcium, such as lime d. Ferric salts used for coagulation

c. Calcium, such as lime

Chlorinating before a microstrainer may cause a sticky, jelly-like coating to form on the microstrainer. What is present in the water that causes this problem? a. Soluble iron b. Soluble manganese c. Slime-producing algae d. Filamentous algae or fungi

a. Soluble iron

Chelation controls ___ __, and sequestration controls __ ___. a. Scale, corrosion b. Corrosion, scale c. Scale, scale d. Corrosion, corrosion

a. Scale, corrosion

What membrane process will remove dissolved solids? a. Microfiltration b. Reverse osmosis c. Nanofiltration d. Ultrafiltration

b. Reverse osmosis

Determine the feed rate for alum in mL/min with the following conditions: Plant flow 16.4 mgd Alum dosage rate 8.35 mg/L Alum percentage 48.5% Alum specific gravity 1.26 a. 139 mL/min of alum b. 359 mL/min of alum c. 460 mL/min of alum d. 589 mL/min of alum

d. 589 mL/min of alum

What scale prevention chemical can loosen existing deposits and cause red-water complaints? a. Silicates b. Sodium hexametaphosphate c. Carbon dioxide d. Sulfuric acid

b. Sodium hexametaphosphate

What is the primary purpose of pressure aerators? a. To remove volatile gasses b. To oxidize organic material c. To oxidize iron and manganese d. To add dissolved oxygen for a more pleasant-tasting water

c. To oxidize iron and manganese

When mechanical equipment is used to dewater alum sludge, it must be pretreated usually using a _ ____, which is a circular tank equipped with a __ ___. a. Sludge thickener, stirring mechanism b. Sludge thickener, sludge recirculation feed pump c. Clarifier, chemical feed pump d. Clarifier, stirring mechanism

a. Sludge thickener, stirring mechanism

What dictates the amount of coagulant needed? a. Giardia and Cryptosporidium b. Turbidity and organics c. Turbidity and Giardia d. TOC and Giardia

b. Turbidity and organics

What two types of rapid mixing methods have efficiencies directly related to flow? a. Baffled chambers and static mixers b. Static mixers and mechanical mixers c. Static mixers and pumps and conduits d. Mechanical mixers and baffled chambers

a. Baffled chambers and static mixers

In the lime-soda ash softening process, _____ are used to help gather the _____ into particles that will readily settle out of the water. a. Coagulant aids, floc b. Coagulants, fine calcium and magnesium particulates c. Coagulant aids, precipitates d. Coagulants, floc

b. Coagulants, fine calcium and magnesium particulates

What will most likely exhaust granular activated carbon first? a. Taste and odor compounds b. Organics c. Chlorine d. Polymers

c. Chlorine

To make sure the gravel has not shifted or moved up into the sand layer, a metal rod should be used to probe the filter on a grid system to locate and record the depth to gravel. At a minimum, how often should this be done? a. Every 6 months b. Once per year c. Every 2 years d. Every 3 years

b. Once per year

What types of caps would be best to use on iron bolts so that the caps become the sacrificial anodes and the iron bolts the protected cathodes? a. Brass b. Magnesium c. Tin d. Copper

Magnesium

A _ ___ is a conical tank in which the softening reactions take place ___ __ as the water passes upward through the unit. a. Clarifier, rather slowly b. Thickener cone, quite rapidly c. Softener reactor, rather slowly d. Pellet reactor, quite rapidly

d. Pellet reactor, quite rapidly

Besides controlling algae using copper sulfate or powdered activated carbon, what other method has been occasionally used? a. Sulfur dioxide b. Sodium thiosulfate c. Calcium sulfate d. Potassium permanganate

d. Potassium permanganate

A 1 ppm alum solution is desired for performing a jar test. If the alum has a specific gravity of 1.25 and is 48.0% alum, how many milliliters are required to make exactly 1,000 mL stock solution? a. 1.6 mL of alum b. 1.64 mL of alum c. 1.65 mL of alum d. 1.67 mL of alum

d. 1.67 mL of alum

At a softening plant, the most severe carryover of sludge in a sedimentation basin occurs when _____. a. High winds are blowing in the direction of the weir b. The sludge is too high and the flow of the water has cut a “river” through it, causing severe short-circuiting c. Incomplete coagulation-flocculation is occurring d. The floc is composed mostly of magnesium hydroxide particles

d. The floc is composed mostly of magnesium hydroxide particles

If there is no pretreatment, what membrane process will remove dissolved organic matter? a. Microfiltration and nanofiltration b. Nanofiltration and reverse osmosis c. Microfiltration and ultrafiltration d. Nanofiltration and ultrafiltration

b. Nanofiltration and reverse osmosis

According to best practices, tip speed of the last flocculator should be about _____ and operate in the range of _____. a. 0.5 ft/s, 0.3 – 0.8 ft/s b. 1.0 ft/s, 0.9 – 1.3 ft/s c. 1.5 ft/s, 1.0 – 2.0 ft/s d. 2.0 ft/s, 1.5 – 2.5 ft/s

b. 1.0 ft/s, 0.9 – 1.3 ft/s

Currently, the zebra mussel population is _____. a. Decreasing in number in most waters in North America b. Slightly decreasing in number in most waters in the United States c. Stable, due to strong control measures d. Spreading to most waters of North America

d. Spreading to most waters of North America

In the lime-soda ash process, what will cause increased solubility of taste- and odor-causing compounds? a. Elevated pH values b. Elevated temperatures c. Reactions between carbonate ions and negatively charged organics d. Ionic bonding of calcium and magnesium carbonates with tannic and fulvic acids

a. Elevated pH values

Calculate the detention time in hours, for the following potion of a treatment plant: Four flocculation basins, each 49.8 ft by 23,9 ft with an average water depth of 10.8 ft; the sedimentation basin is 128 ft long, 79.8 ft wide, and has an average water depth of 10.1 ft; and the flow is 17.2 mgd. a. 0.87 hr b. 2.18 hr c. 4.37 hr d. 1.61 hr

d. 1.61 hr

The sediment from presedimentation systems can be kept if samples are collected _____. a. Through core sampling b. Randomly throughout the basin as grab samples c. As composite sampling throughout the basin ‘ d. And vacuum sealed in glass containers

a. Through core sampling

When alum is added to water, it causes the pH to _____, and when ferric salts are added to water, it causes the pH to _____. a. Increase, increase b. Decrease, decrease c. Increase, decrease d. Decrease, increase

b. Decrease, decrease

Lime slakers should be equipped with a __ ___ that will stop the lime feed before __ ___. a. Temperature override device, freezing occurs b. Water flow gauge, the lime is over-diluted c. Temperature override device, dangerous temperatures are reached d. Scale, it overfeeds the lime

c. Temperature override device, dangerous temperatures are reached

Chlorite monitoring is required only for systems using _____. a. Ozone b. Sodium hypochlorite c. Chloramines d. Chlorine dioxide

d. Chlorine dioxide

Advanced Treatment Process Flashcards

(104 cards)