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TEXAS WASTEWATER CLASS D EXAM ALL 350
QUESTIONS AND CORRECT ANSWERS ALREADY
GRADED A+ LATEST 2024-2025 UPDATE
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
- softening 1 / 4
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- 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
Chemically, water is made of ________. - ANSWER-2 atoms of hydrogen and 1 atom of oxygen
The hydrologic cycle is ________.
- nature's way of recycling water
- equipment used to measure distances
- the way water filters through the earth
- the process by which water runs into rivers and lakes - ANSWER-a. nature's way of recycling
water
The quality standard for public water supplies is based on the use of water for ________. - ANSWER-drinking 2 / 4
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Most surface water is low in minerals, gases, and ________.
- algae
- turbidity
- dissolved solids
- bacteria - ANSWER-c. dissolved solids
Quality water has low amounts of color, turbidity, solids, and ________.
- oxygen
- taste and odor
- hydrogen
- all listed - ANSWER-b. taste and odor
Pretreatment includes lake destratification, control of algae, debris removal, presedimentation, aeration, ________, and activated carbon adsorption. - ANSWER-chemical oxidation
Copper sulfate in dosages of ________ and approved algaecides control algae blooms.
- 10 to 50 mg/L
- 1 to 5 mg/L 3 / 4
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- 0.1 to 0.5 mg/L
- 0.01 to 0.05 mg/L - ANSWER-c. 0.1 to 0.5 mg/L
The most effective treatment for taste and odor is adsorption with ________. - ANSWER- activated carbon
Lime is applied to water to adjust ________. - ANSWER-adjust pH or alkalinity
The process of using chemicals to clot particles together is called _____ and _____. - ANSWER- coagulation and flocculation
Detention time in sedimentation basins must be at least ________ hours to allow floc to settle.
- ANSWER-6
Factors affecting sedimentation are weight of the floc, ________, detention time, and short- circuiting.
- water temperature
- water velocity
- taste and odor
- a and b - ANSWER-d. water temperature and water velocity
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