In rural road construction, the use of which of the following is preferred for ensuring environmental sustainability or to reduce carbon footprint ?
- 1.Copper slag
- 2.Cold mix asphalt technology
- 3.Geotextiles
- 4.Hot mix asphalt technology
- 5.Portland cement
Select the correct answer using the code given below :
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Answer: A. Copper slag (a waste re-used), cold mix asphalt (no heating needed) and geotextiles (less material needed) are promoted as green technologies for rural roads under PMGSY. Hot mix asphalt needs heating, and Portland cement production emits a lot of CO2. So 1, 2 and 3.
Watch for: Hot mix sounds standard and modern, but cold mix is the greener option.
Why the other options are wrong
- B. Wrong because hot mix asphalt needs heating, which uses more fuel.
- C. Wrong because hot mix and Portland cement have large carbon footprints.
- D. Wrong because Portland cement has a high carbon footprint.
Source to check: PMGSY Guidelines on use of New and Green Technologies (NRIDA, pmgsy.nic.in); IRC SP:100 (cold mix technology)
Answer from the official UPSC key. Written and fact-checked by AI against the official key. Spotted a mistake? Report it.