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TEXAS WASTEWATER C LASS D NEWEST 2024-2025
ACTUAL EXAM COMPLETE 300 QESTIONS AND
CORRECT DETA ILED ANSWERS (VERIFIED
ANSWERS) |ALREADY GRADED A+
One of the most important purposes of a public water supply is
_______.
- swimming
- landscape watering
- car washing
- firefighting - ANSWER- d. firefighting
Organic matter includes ________.
- sand
- plants, animals and humans
- minerals
- all listed - ANSWER- b. plants, animals and humans
The most important treatment process is ________, which destroys disease-causing organisms.
- filtration
- disinfection 1 / 4
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- softening
- fluoridation - ANSWER- b. disinfection
Public water systems are required to compile a monthly report showing ________.
- rate increases
- accidents
- dates of dead-end flushing
- disciplinary action - ANSWER- c. dates of dead-end flushing
Most groundwater is relatively free of suspended matter, but ________ can be a major problem in surface water. - ANSWER- turbidity
Color in a public water supply should be less than _____ units. - ANSWER- less than 15 units
Chemical characteristics of water include hardness, pH, solids, and ________. - ANSWER- gases
Water is considered hard when it exceeds ________ mg/L of calcium carbonate. - ANSWER- 100 (may vary depending on who you talk to) 2 / 4
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A gallon of water weighs _____ pounds and 1 mg/L equals one ________. - ANSWER- water weights 8.34 pounds
- mg/L equals one part per million
Hydrogen sulfide is heavier than air, colorless, flammable, toxic, and has a ________ odor. - ANSWER- rotten egg (unless you get a dose that's so heavy it numbs your sense of smell)
Excessive nitrates in drinking water can cause ________ syndrome in infants. - ANSWER- blue baby syndrome
Excessive amounts of fluoride may cause ________ or staining of teeth. - ANSWER- mottling
Trihalomethanes and haloacetic acids are byproducts of chlorination and may increase ________ risk. - ANSWER- cancer
The action level for copper is _____ mg/L and for lead it is _____ mg/L. - ANSWER- copper is 1.3 mg/L lead is 0.015 mg/L
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_____ are underground, water-bearing formations yielding useful quantities of water. - ANSWER- Aquifers
The quantity of water a formation yields depends on the thickness and _____ of the formation. - ANSWER- permeability
Problems caused by _____ are declining water levels and subsidence. - ANSWER- overpumping
Well _____ and cementing protect the well from collapse and surface contamination. - ANSWER- Well casing
The purpose of the well screen is to keep out birds and insects.(true/false) - ANSWER- false (the well screen keeps out sand; the well vent screen keeps out birds and insects)
The most important feature of the well screen is the length.(true/false) - ANSWER- false (the mesh size is the most important feature)
The _____ of the screen is determined by the size of the aquifer material, the size of the gravel in the gravel pack, and the type of well development. - ANSWER- mesh size
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