Controlling Pollution

Challenges to clear

• Answer all five situations.
• Answer the fertilizer case correctly — more is not better.

The task

Pollution cannot be totally controlled, but several steps curtail it. Pick the step that actually fits each situation.

What this lesson covers

• You are sitting in a car at a long red light. The driver keeps the engine running because the signal will change soon. Best choice: Switch the engine off — engines should be off at red lights and whenever the vehicle is not in use — Switching off engines at traffic signals is one of the named control measures, along with using unleaded petrol and compressed natural gas in automobiles.
• A dye factory discharges its liquid waste straight into the river beside it, and offers to build a much taller chimney to make up for it. Best choice: The effluent itself must be treated before it is discharged into the water body — Treating industrial effluents before discharge is the listed measure, and larger habitations should also have sewage treatment plants, with septic tanks in houses.
• A farmer doubles his dose of nitrate fertilizer to raise the yield, and plans to spray DDT as well. Best choice: Use compost instead of chemical fertilisers and be judicious with pesticides — Greater use of compost in place of chemical fertilisers, and judicious use of pesticides, are both listed control measures — the basis of organic farming.
• A canteen hands out disposable straws, cutlery and polythene carry bags with every order, and burns the day's waste in the yard each evening. Best choice: Reduce, reuse and recycle — refuse the carry bags, use refillable bottles, and send plastic, metal and glass for recycling — Single-use plastic may take hundreds of years to break down and chokes landfills, drains and rivers before it is swallowed by marine animals. The three Rs and recycling of plastic, metal and glass are the answer.
• A newspaper reports that a state has just enforced BS IV emission norms, and a reader asks what the point of such rules is. Best choice: Bharat Stage norms cap the sulphur and nitrogen oxides a vehicle may emit, and force cleaner fuels as well as cleaner engines — The Euro Bharat standards were first set in 2000 and upgraded through BS II, BS III and BS IV, which was enforced nationwide on 1 April 2017. They are set by the Central Pollution Control Board, and refineries must supply cleaner fuel for them to work.

Hint

Match the measure to the medium. Chimneys, CNG and switched-off engines are for air; effluent treatment, sewage plants and septic tanks are for water; compost, recycling and landfills are for soil. Swachh Bharat Abhiyan, launched on 2 October 2014, covers the streets and the waste management behind all three.