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This set of MCQs helps students to learn about natural methods of wastewater disposal which are biological treatment systems that require no or very little electrical energy; instead, they rely on entirely natural factors such as sunlight, temperature, filtration, adsorption, sedimentation, biodegradation, etc., to treat wastewater or fecal sludge.
Which of the following is a prime lake pollutant?
The turbulence decreases the DO content of water.
The dilution factor is 400. What should be the type of treatment given to the water?
The tolerance limit of oil and grease of sewage to be disposed on land is ____________
The tolerance limit of pH value of sewage to be discharged into sea water is ____________
The pollution zones in the river are divided into how many types?
In which pollution zone of the river, growth of algae reappear?
In which pollution zone of the river, the dissolved oxygen reduced to 0?
Which is the third zone of pollution in the river?
In which pollution zone of the river, water retains its original dissolved oxygen concentration?
The fishes were present in the river, but algaes were not able to survive. What is the zone of pollution of the river?
In which pollution zone of the river, the concentration of D.O reduced to 40%?
The dilution factor is expressed by _____________.
Volume of diluted sample + Volume of sewage
Volume of diluted sample / Volume of sewage
Volume of diluted sample – Volume of sewage
Volume of diluted sample* Volume of sewage
The tolerance limit of BOD of sewage to be disposed on land is ____________.
100ppm
200ppm
500ppm
400ppm
