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238 Cards in this Set
- Front
- Back
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Hard water scale is usually caused by?
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(CaCO3) |
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What bolt do you adjust on a sludge collector bar screen?
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Vertical Capstand |
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What is the most probable cause of pinging from a pump?
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Cavitation |
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Which of the following is the primary function of couplings? |
Compensate for alignment changes |
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What tools are used to check parallel and angular alignment of the coupling on a pump or meter?
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A feeler gauge, dial indicator, calipers |
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High Rate filtrate gallons/min/ft^2 for Fe & turb removal dual media depths? |
Total - 30 inches Sand - 10 to 12 inches Anthracite - 18-20 inches |
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Contact time
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At least 30 mins for surface water, ground water 15 mins |
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A chlorine evaporator maintains a water bath at? |
170 to 180 degrees Fahrenheit. |
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How much alkalinity is required for each milligram per liter of alum added to raw water?
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0.5 mg/L |
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At what temp does the fusible plug in a gas cylinder melt? |
70 - 73.9 degrees Celsius |
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Indigo Test
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Ozon residual |
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Stratification
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Formation due to the temperature of separate layers in a lake or reservoir |
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Mixture of air and gas is considered hazardous when the mixture exceeds what percentage of the LEL?
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(LEL) Lower Explosive Limit 10% |
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Filter Disinfection |
Cl 2 residual >25 mg/L after 12 hours contact not <15 mg/L |
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Terminal Head Loss |
When head loss is such that water will not pass through the filter |
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What is the titrant or the ampometric chlorine titration? |
Phenylarsine Oxide |
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Membrane Filters CIP Chemicals
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Clean In Place Acids Oxidants Surfactants |
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What is the usual strength of Sodium Hypochlorite?
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5 to 15% |
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The 3 Stratification Layers? |
Metalimnium Hypolimnium |
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Why control Iron and Manganese SMCL's?
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2)They can promote the growth of bacteria which can cause taste and order problems Mn - 0.05 mg/L Fe - 0.3 mg/L |
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What Determines a water plants classification?
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Amount of water produced |
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What is cavitation? |
The creation of vapor bubbles due to partial vacuum created by incomplete filling of the pump caused by rapid change in velocity or direction of the water which can cause pitting. |
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Chlorine leaks can be detected by using?
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Chlorine detector at 0.3 PPM |
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Most important fact about lubricating equipment is? |
Flash Point Lubrication |
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UV Disinfection Solarization |
Drop in UV effectiveness due to clouding of the glass |
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-Chemicals for test -End Points -Significance |
2) A waters capacity to resist a change in PH. Chemicals: -Sodium Thiosulfate -Methyl Orange - 4.5 -Phenolpthalein - 8.3 |
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95% of all turbidity measurements each month for a 10,000+ population system must be less than or equal to?
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0.3 NTU |
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What is the minimum Cl 2 level in the distribution system? |
0.2 PPM |
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Rotameters measure what?
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Gas flow (Cl
2) |
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Apparent Color vs True Color |
True Color will not filter |
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CIP Chemicals |
Oxidants Surfactants |
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3 Phase AC If pump flows backwards what should be done? |
Shut down and switch any two leads |
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In membrane filtration, what chemical is sued as a scale inhibitor?
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(scale inhibitor) |
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All Dead Ends whall have? |
Blow off valves of flush mechanisims |
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When both Cl2 and Polyphosphate are added to a well, which should be fed first?
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Phosphate |
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4 zones of the sedimentation basin
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Settling Sludge Outlet |
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What is the smallest of all contaminants?
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Virus |
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When chlorine is added to water what 2 acids are formed?
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2) Hydrochloric Acid |
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Representative sample
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Sample which contains basically the same constituents as the body of water from which it is taken. |
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Microbiological Records must be kept for how long?
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-routine distribution -line repairs -new line |
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Lead (Pb) & Copper (Cu) records must be kept for how long?
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(Cannot be collected in a plastic bottle) |
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What causes air binding? |
When air comes out of solution as a result of low pressure and high temperature
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What is the Piezometric Surface? |
Height that water rises in a confined aquifer. |
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Density of Cl2 gas? 1 volume of liquid gas expands who many times? |
Expands - 460 times |
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- Chemical Used - Human Smell Detection |
Ammonia Solution Vapor 0.3PPM Human Detection |
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What are the 5 means of preventing backflow?
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Reduced Pressure Double Check Valve Pressure Vacuum Breaker Atmospheric Vacuum Breaker |
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THM's HAA5 |
Haloacetic Acids - 5 acids, 0.060 mg/L MCL |
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Disinfection of a new pipe line |
Residual >25 mg/L after 24 Hours, there must be a detectable residual |
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As a general rule water pipes should be separated from sewer pipes by a horizontal and vertical distance of? |
Vertical - 1 ft |
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A community water system serves at least ____ service connections or ____ people ____? |
25 people all year |
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Max detention flocculator? |
Flocculator - 30 mins minimum 45 mins recommended |
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List 3 ways of removing odors from water |
2) Oxidation 3) Adsorption with granular activate compounds |
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What two elements cause hard water? |
(Hard Water >100 mg/L CaCO3, Soft Water <65 mg/L CaCO3) Magnesium |
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Supernatant
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The area between the scum on the water surface and the sludge on the bottom in a basin |
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What is an adit? |
An intake structure |
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Sweep coagulation
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Achieving the desired PH range by overdosing the coagulant |
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Bac-T on a new line must be taken? |
At each end avert 1500 feet and at every T. |
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How much Cl2 will the sodium thiosulfate in a Bac-T bottle remove?
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Up to 10 parts
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Hydropneumatic System |
A system that pumps water into a sealed tank that also contains compressed air. Used by small systems. |
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Water Hammer |
A rapid increase in (surge) pressure in a water system. |
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(Curb Stop) |
A device that starts and stops flow by means of a "ball" with a hole in it. |
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Chemical Analysis Records must be kept for how long?
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- Inorganics - SOC's & VOC's -THM's and HAA5's -Radionuclides |
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E. O. P. |
Should be changed when there is a: -Change in the water system configuration -At least every two years |
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Total Coliform Rule |
-at the original site -within 5 upstream -within 5 downstream MCLG = 0 MCL = based on samples taken 40 for 1 up to 5% |
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H2S can be a problem in what type of water? How is it detected? What does it cause? |
Rotten Eggs Structural corrosion |
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For every mg of Iron, feed ____ mg of KMnO4. SMCL: _____ Taste: _____ ____ O2 for aeration |
SMCL: 0.3 mg/L Taste: 0.5 mg/L 0.14 02 for aeration to get rid of Fe |
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Ca(OH)2 Na2CO3 NaOH |
Ca(OH)2 : Lime NaHCO : Sodium Bicarbonate Na2CO3 : Soda Ash or Sodium Carbonate Caustic Soda |
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Which laboratory tests are used to monitor the coagulation and flocculation process?
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Jar test, PH test, Turbidity |
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Reccord Keeping: MOR's MSDS Plant SOP Sanitary Surveys Storage Tank Inspection Tank Maintenance Turbidity Analysis |
MSDS : 30 Years Plant SOP : Keep until updated Sanitary Survey : 10 years Storage Tank Inspection : 5 years Tank Maintenance : Life of the Tank Turbidity Analysis : 5 years |
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Lantern Ring
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A perforated ring placed around the pump shaft in the stuffing box. Water from the pump discharge is piped to this ring. The water forms a liquid seal around the shaft and lubricates the packing. |
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Calcium & Magnesium precipitate out of solution at what respective pH's? |
Magnesium: 10.8 Magnesium Hydroxide (Mg(OH)2) |
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Globe Valve
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Most common use is a standard faucet. A small disk is raised and lowered onto a seat to start, stop or throttle flow. |
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MBAS (Methyl Blue Active Substance) SMCL |
0.5mg/L |
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What kind of device can be used to prevent a cross-connecting between potable and an auxiliary source?
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Reduce pressure backflow preventer |
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Iron bacteria is called? |
Gallionella |
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E. O. P. |
Emergency Operation Plan |
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Disinfecting a new line residual? |
25PPM |
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Disinfecting a new well residual? |
50PPM |
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What is aeration?
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A gas transfer used in water treatment to dissolve air into the water therefore oxidizing Fe. |
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Aeration effectiveness is dependent on _____ to ____ ____.
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air to water ratio (Min: 25:1, Max: 80:1) |
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The membrane module is pressurized to approx. ____ psi from the feed side. |
15 PSI |
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The minimal loss of head pressure during an integrity test is? |
1 PSI every 5 minutes. |
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Public Notification Rule
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Tier 2: Within 30 days (month). (Mail or Direct Deliveries) Tier 3: 12 months (year). Can be combined into an annual notice including the CCR. |
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Direct Filtration Turbidity must be less than ____ for Direct Filtration. |
Operated in mixed or dual media no higher than 2 gpm/ft2. |
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If the flanges are not parallel and vertical on a centrifugal pump what problem occurs?
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Every rotation throws tremendous extra load on bearings which results in shortened pump life. |
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Composite Sample
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A water sample composed of a collection of individual samples obtained at regular intervals from a particular source. |
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What is the difference between a direct and indirect cross-connection? |
Indirect - is only subject to back siphonage. |
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What information is on the lock out tag when equipment is locked out?
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Signature of person that preformed the lockout. |
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Who is responsible for informing the public on water issues? |
The designated spokesperson. |
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Which type of fire extinguisher should be used on electrical fire? |
CO2
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When draining a water tank or sedimentation basin for cleaning what should be considered?
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Water table level |
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Which is the best aerator for VOC (Volatile Organic Compound) removal? |
Packed tower |
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All community water systems serving 50 connections must have duplicate _____ for _____, ____, and ____; and must have _____ of distribution storage based on the past _____.
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pump, raw, finished, and distribution 24 hours, 12 months |
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List four factors that influence disinfection.
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2) Temperature 3) Contact Time 4) Concentration of disinfection |
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In order to make a fluoride "slurry" the water must be softened to _____? |
<75 mg/L of hardness as CaCO3(Calcium Carbonate). |
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What temperature and pressure should an autoclave be set?
|
Pressure: 15 PSI |
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Manganese SMCL
|
0.05 mg/L |
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Ca(OH)2 NaHCO Na2CO3 NaOH |
Sodium Bicarbonate Soda Ash or Sodium Carbonate Caustic Soda |
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Fluoride MCL and SMCL |
SMCL: 2.0 mg/L |
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Float Valve
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Controls reservoir tank levels. Relies on float to start/stop inflowing water. |
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Oxygen Range for confined spaces |
Combustible: 23.5% Normal: 21% Deficient: 19.5% |
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Temporary Hardness |
Carbonate hardness is non-permanent hardness which can be removed by heat. |
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Permanent Hardness
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Noncarbonate hardness |
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What preservative is required for a fluoride sample?
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None |
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All vents on wells, springs, storage tanks, overflows and clearwells shall be properly screened with? |
#24 Stainless steel mesh |
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Coagulant aid has what effect on floc? |
Few pieces of large floc and less overall floc. |
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Types of dry feeders in TN?
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Gravimetric and Volumetric |
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What is the most important method of preventing backflow?
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2x the diameter of the pipe or no less than an inch. |
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A high voltage transformer is? |
440 Volts or higher |
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What are the categories of membrane filters by pore size in order from biggest to smallest? |
Ultra Filtration (UF) Nano Filtration (NF) Reverse Osmosis (RO) |
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Wear Rings
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Rings made of bronze or brass placed on the impeller and/or casing of a centrifugal pump to control the amount of water that is allowed to leak from the discharge to the suction side of the pump. |
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High rate filter Rates
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4.0 gpm/ft2 |
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Langelier Index
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Measure of a solution ability to dissolve or deposit calcium carbonate. Related to the depositing of a calcium carbonate film or scale.
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Algea causes what in the distribution system?
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Tate and odor |
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Odor complaints start at?
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5 TON (Threshold Odor Number) |
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What group of algae are usually associated with "Blinding the filters?" |
Diatoms |
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What is the major cause of short circuiting in a sedimentation basin?
|
Poor inlet baffling.
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What color does the oxidant Potassium Permanganate (KMnO4) turn at it's endpoint? |
Yellow |
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When air is used to generate ozone, an air dryer should be used to reduce the?
|
Nitrous oxides |
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Sludge from alum and lime can cause?
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Sewer blockages |
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Trace the conventional water treatment process
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What is the minimum and maximum air-to-water ratio for Packed Tower Aerators?
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Maximum: 80:1 |
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Altitude Valve |
Activated by reservoir level/pressure to open and close. Reduces the chance of overflows. |
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Ozone generators produce what % of ozone? |
Pure ozone: 5 to 7% |
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Iron (Fe) Manganese (Mn) Lead (Pb) Copper (Cu) Nitrate (NO− Nitrite (NO− Nitrate and Nitrite Fluoride (F) |
Iron (Fe): 0.3 mg/L SMCL Manganese (Mn): 0.05 mg/L SMCL Lead (Pb): 0.015 mg/L (PPB) Action Level Copper (Cu): 1.3 mg/L MCL Nitrate (NO− Nitrite (NO− Nitrate and Nitrite: 10 mg/L Fluoride (F): 2.0 mg/L SMCL 4.0 mg/L MCL |
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Calcium and magnesium precipitate out of solution at what respective pH's?
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Magnesium: 10.8 Magnesium Hydroxide (Mg(OH)2) |
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Slake and Unslaked Lime
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Slake Lime - used at small plants (Ca(OH)2) Unslaked Lime (Quick Lime) - Usually comes in bulk deliveries, never store with Alum |
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Pressure Relief Valve
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Responds to pressure variations at their inlets. Open rapidly when there is a raise in pressure above set points and vent to the atmosphere. |
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What compound is measured and what titrant is used in the hardness titration?
|
Calcium Carbonate (CaCO3) 0.02N Ethylenediaminetetraacetic acid (EDTA) Turns the color from red to blue |
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UV lamps output drops _____ in the first _____ hours.
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30-40% in the first 7,500 hours
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Dual Media Filters Sand and Anthracite Size? |
Sand: 0.35mm to .55mm Anthracite: 0.8mm to 1.2mm |
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Air Valves
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Allows air to vent from a water system |
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List 5 Properties of Chlorine Gas |
2) 2.5x heavier than air 3) Expands 460 times that of air 4) Non Flammable 5) Supports combustion |
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Ground Water contact time? Operator must be within? |
30 minutes |
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Residual ozone is measured by what?
|
Indigo Test |
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Zeolite
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Media in an ion exchange system |
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What measures the amount of oxidizing agent? |
Iodometric Method DPD |
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When supplied with air, ozone generators will produce approximately what percent ozone?
|
1% to 3% |
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Filter Media Mono Dual Mixed |
Mono: Sand Dual: Anthracite (on top of filter) Mixed: Anthracite, Sand, Garnet |
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What two reagents are sued to measure Cl2 residual?
|
DPD |
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Van Der Waals Force |
The force that draws particles together, the aim of coagulation.
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Surface Water vs. Ground Water |
GW: Dissolved gases, dissolved solids, lower level of color, high hardness, no microbial contamination, no organic/THMs |
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Which chemical increases the Bicarbonate Alkalinity when added to water? |
(NaHCO |
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What is TISAB used for and what does it stand for?
|
Total Ionic Strength Adjustment Buffer |
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What problem do down-sloping suction pipes cause in centrifugal pumps?
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Air pockets could be drawn into the pump and cause a loss of suction |
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Three things that affect the need to backwash
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2) Turbidity 3) Head Loss (8.0) |
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gallons/min/ft2 for turbidity and iron removal? Depth? |
Turbidity: 2.0 gallons/min/ft2 Iron: 3.0 gallons/min/ft2 Depth: 30 inches Sand = 0.35mm - 0.55mm |
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Surface Water Contact Time?
|
30 minutes |
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What causes the UV light bulb to lose it's ability to transmit light? |
Solarization |
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what is an Impeller |
The rotating set of vanes that force water through the pump. |
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Causes of short filter runs?
|
Filter aid overdosing, excessive filtration rates, excessive mudball formation, clogging of the under drain system. |
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What are the 4 categories of contaminants?
|
Physical - Temperature, taste, color, odor, turbidity Chemical - Inorganics, organics, mineral Biological - Virus, Bacteria, Protozoans Radiological |
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Ozone generators must be supplied with?
|
Very dry air
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Icing or freezing of a chlorine cylinder is caused by? |
Too high feed rate |
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Which laboratory tests are used to monitor the coagulation process? |
Jar Test pH Test Turbidity Test |
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Recarbonation basins are used to stabilize water after? |
Softening |
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Which chemical is used to soften water through chemical precipitation? |
( Ca(OH)2 ) |
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What is the optimal maximum water velocity through pipes under normal operating conditions?
|
5 feet per second |
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The amount of water in a water-bearing formation depends on the?
|
Porosity of the formation |
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What is the primary origin of coliform bacteria in the water supplies? |
Fecal contamination by humans and animals? |
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What type of ductile iron pipe joint is primarily used?
|
Ball and Socket |
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Slow sand filters are cleaned by? |
Scraping about 1 inch of sand off the top |
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When is the best time to conduct an audio leak survey? |
Night |
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What is the killing or inactivation of pathogenic organisms in water called? |
Disinfection
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Carbon Dioxide is used to reduce?
|
pH
|
|
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Galvanic Series |
A list of metals presented in the order of the tendency to corrode. |
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Bypass Valve
|
Pressure on both sides of a larger gate to ease the operation of that gate. |
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When lime and sulfuric acid react what do they form?
|
Salt |
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To reverse the direction of any 3 phase motor?
|
Switch any two legs of the circuit. |
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Which chemical is used to remove residual chlorine from water? |
(Na2S2O3) |
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|
What chemical are saturators best suited for? |
Sodium Fluoride (NaF), because of it's constant saturation point. |
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What are tiny indentations high on the shoulder bearing or race called? |
Brinelling |
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|
UV Wavelength Range
|
250 nm - 265 nm |
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What type of emergency repair kit is used for a 150lb chlorine cylinder?
|
Type A |
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What water source is most likely to incur algae blooms? Eutrophic, Mesotrophic, or Oligotrophic?
|
Mesotrophic has moderate nutrients and aquatic life Oligotrophic has the lowest nutrients and aquatic life |
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How can the removal of Hydrogen Sulfide (H2S) from water best be accomplished?
|
Lowering pH and Aeration
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What is Zeolite?
|
The Media in an Ion Exchange System
|
|
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What measures the amount of oxidizing agent? |
Iodometric method
|
|
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Turbidity measurements must be reported within how many days after the end of each month?
|
10 days |
|
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What are the three types of water rights?
|
Appropriative: the first person to take a quantity of water from a water source for "beneficial use"—agricultural, industrial or household —has the right to continue to use that quantity of water for that purpose Prescriptive: Some crap that only applies to California |
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How long must you keep logs for individual filter bed turbidity?
|
3 years |
|
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What broth is used in the membrane filter technique for total coliform? What is the incubation time and temp? What color is a positive?
|
M-Endo Broth 35°C +/- 0.5° Red with a green-gold metallic sheen |
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|
List three physical means of disinfection
|
Heat Ultrasonic waves |
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|
Which of the following is not considered to be an unethical act? A) Accepting bribes B) Accepting gifts C) Providing false or misleading information D) Whistleblowing |
Whistleblowing |
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The Maximum Residual Disinfectant Level (MRDL) for chlorine is?
|
4.0 mg/L |
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|
What is the MCL for odor?
|
3 Threshold Odor Number (TON) |
|
|
What is the SMCL for Manganese?
|
0.05 mg/L |
|
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What is the minimum detention time for conventional sedimentation basins used for turbidity removal?
|
4 Hours |
|
|
What is the main purpose of priming a pump? |
To replace the air inside the pump with water |
|
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A filter should be backwashed when it has high? |
Head Loss |
|
|
What is the primary health risk of Trihalomethanes (THM)? |
Cancer |
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What main characteristic of raw water enables blue-green algae to grow? |
Presence of nutrients |
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What type of level sensor is required on an air supply? |
Bubbler tube |
|
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What contributes to the creation of algae blooms? |
Increased nutrients
|
|
|
A 2 inch tap can be made through a saddle on which ductile-iron pipe size?
|
6 inch |
|
|
Free chlorine residual times are based on a contact time of?
|
10 minutes |
|
|
The capability of a water or chemical solution to resist a change in pH is called? |
Buffering Capacity |
|
|
What is the odor detection limit for chlorine gas?
|
0.3 PPM |
|
|
A foul, rotten egg odor from an aeration unit is an indication that the source water contains? |
(H2S) |
|
|
How long should a new tank be disinfected before a water sample is collected for coliform analysis?
|
24 Hours |
|
|
The most common water complaints are taste, odor and? |
Colored water |
|
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What do long filter runs tend to cause?
|
Slime growths |
|
|
What is the filter medium in DE filters?
|
Diatomaceous Earth |
|
|
What type of pipe is generally used in the construction of very large water mains? |
Steel |
|
|
What is a cathode?
|
Negative Pole of an electrolytic cell or system |
|
|
What metals are most likely to leach from household plumbing and cause a health hazard? |
Lead (Pb) and Copper (Cu) |
|
|
Samples collected at regular intervals and combined in equal volume with each other are called what? |
Time Composite Samples |
|
|
A main break may cause loss of pressure which in turn may result in what? |
Contamination of the system by backsiphonage |
|
|
What style of curb box fits loosely over the curb stop and meter? |
Arch Style |
|
|
What is schmutzdecke? |
A sticky mat of matter that has formed on the surface of a sand filter
|
|
|
Copper Sulfate (Cu2SO4) is used in surface water reservoirs to control?
|
Algae
|
|
|
THM's are usually associated with?
|
Water with organics that have been chlorinated |
|
|
Fire hydrants should generally be set back from the curb at least? |
2 Feet |
|
|
Chlorine neutralization is necessary when a treated sample is to be analyzed for?
|
Bacteria |
|
|
What is the name of the pipe that serves as the inlet and outlet to an elevated tank? |
Riser |
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|
How is a utility's annual average day demand determined?
|
Total water use for a year divided by 365 days |
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As water temp increases, the disinfection action of chlorine will? |
Increase |
|
|
What condition must exist for a push joint to be used?
|
The pipe must be pushed on at an angle |
|
|
Which substances pose an immediate health threat whenever standards are exceeded?
|
Coliform and Nitrate |
|
|
What is the minimum pipe diameter of a water main for a fire hydrant? |
6 inches |
|
|
Coagulation, flocculation and filtration is the best means to remove giardia lamblia. |
True
|
|
|
When UV radiation is used to inactivate microorganisms, what are the optimal wavelengths?
|
250nm to 265nm
|
|
|
What chemical oxidant would be most effective in removing color and controlling taste and odor? |
Ozone |
|
|
Excessively hot bearings are most probably due to what? |
Overlubrication |
|
|
What is a pump casing? |
The enclosure surrounding a pump impeller, into which the suction and discharge ports are machined. |
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Backflow through a cross connection due to backsiphonage can be caused by what?
|
Broken mains or hydrants |
|
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The amount of air water can hold is _____ proportional to the temperature.
|
Inversely |
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Which oxidant is a bluish toxic gas with a pungent odor?
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Ozone |
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The advantage of using the oxidant ozone?
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Little effect on pH |
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What are the weights of chlorine receptacles both empty and full? |
50lb Cylinder: 50lbs empty, 250lbs full 1 Ton Cylinder: 1650lbs empty, 3700lbs full Rail Car: Empty varies by size, Up to 6000lbs full |
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Cl2 gas supply lines should be replaced at least?
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Annually |
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Coagulation occurs during the first?
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1 to 5 seconds |
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What is the effective pH range of Alum?
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5.8 - 8.5 |
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What is nitrification?
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When ammonia becomes nitrites and the nitrates
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How long should you keep new tap records? |
Until the next sanitary survey or 3 years |
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The primary purpose of check valves is o prevent what? |
Water from flowing in two direction |
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What is the maximum operating temperature of a mechanical seal?
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71°C |
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How often should tanks be inspected?
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Tanks should be professionally inspected every 5 years by draining or by robot |
