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 :

This snippet states that plastic waste can be used for road construction as per guidelines, showing roads are a recognized channel for reusing waste to reduce environmental burden.

A student could combine this with knowledge that cold mix methods can incorporate waste plastomers at lower temperatures to judge if cold mix enables such recycling with lower emissions.

It gives the pattern of substituting conventional materials (e.g., replacing cement with fly ash) to reduce cost and environmental impact in construction.

One can analogously consider whether cold mix (which may reduce thermal energy use) is a similar material/technique substitution that lowers carbon footprint in rural roads.

The excerpt outlines requirements for 'ecologically safer roads' including appropriate construction techniques and disposal of debris to avoid ecological harm.

A student could assess whether cold mix asphalt aligns with these 'ecologically safer' techniques (e.g., less thermal disturbance, easier disposal/recycling) to infer possible sustainability benefits.

This discusses black carbon and notes that technologies exist today to reduce black carbon emissions, linking construction technology choices to air-pollution/health outcomes.

Using basic knowledge that hot asphalt production emits combustion-derived black carbon, a student might test if cold mix (which uses less heating) could reduce such emissions.

Describes the scale and significance of rural roads (80% of total road length) and regional constraints affecting rural road construction.

Knowing rural roads are numerous and often in sensitive/remote areas, a student could weigh whether lower-emission, lower-equipment methods like cold mix are operationally preferable and more sustainable in those contexts.

Recommends bio‑engineering and appropriate techniques in road design to treat slope instabilities and avoid adverse ecological impacts—shows a pattern of preferring low‑impact / specialised techniques in sensitive rural/hilly road works.

A student could infer that geotextiles (a specialised technique for slope/stabilisation and drainage) might similarly reduce ecological damage compared with heavy earthworks, and then check geotextile functions against slope protection needs.

Specifically promotes use of plastic waste for road construction per guidelines—gives an example of reusing synthetic materials in roads for environmental gain.

A student could extend this to consider geotextiles (often polymer/plastic based) as a reuse/utility of plastics that may divert waste and reduce raw material demand, then compare lifecycle impacts.

Provides the rule/example that substituting conventional materials (e.g., replacing cement with fly ash) reduces construction cost and is presented as environmentally preferable.

By analogy, a student could assess whether geotextiles replace or reduce heavier, carbon‑intensive materials (e.g., thick aggregate layers), estimating potential carbon savings from such substitution.

Lists rural environmental problems including soil erosion and degradation—issues that road construction can exacerbate and that protective measures can mitigate.

A student could link geotextiles' erosion control and soil‑stabilisation roles to reduced environmental degradation, then infer likely sustainability benefits in rural contexts.

States the general rule that development options should be harmonised with environmental concerns and that environmental consequences must be accounted for early in project design.

A student could use this principle to justify evaluating geotextiles in environmental impact assessments (including carbon accounting) when choosing road construction methods.

Mentions promoting use of plastic waste for road construction per Indian Road Congress guidelines — shows road-construction materials/techniques are chosen for waste-utilisation and environmental aims.

A student could compare the lifecycle emissions and waste-diversion benefits of plastic-modified or waste-based pavements versus conventional hot mix asphalt to judge which is greener.

Describes use of fly ash as a substitute material in road works and embankments — example of material substitution in construction to reduce cost and resource use.

One could extend this to compare emissions embodied in fly-ash-containing mixes vs. bitumen-dominated hot mix asphalt (considering production and transport) to assess carbon footprint.

Stresses that road projects (especially in sensitive areas) require environmental impact assessment and design measures (bio‑engineering, debris disposal) — implies construction technique choice is evaluated on ecological grounds.

A student could use EIA criteria (air emissions, disturbance, waste) to see if hot mix plants and paving operations meet sustainability thresholds compared with alternative low-temperature or cold-mix technologies.

Explains that asphalt/bitumen is a petroleum product used for road surfacing — links road surfacing material to fossil fuel feedstocks and associated carbon emissions.

Knowing asphalt is fossil-derived, one can infer production and heating in hot mix will have fossil-fuel-related CO2/black carbon emissions and compare that to non-petroleum alternatives or cold processes.

Lists measures to control black carbon (e.g., cleaner fuels, reducing thermal power) — provides context that combustion-related processes are significant black carbon sources.

A student could treat hot mix production (which involves high-temperature heating) as a combustion-related source and use these measures as a checklist to evaluate whether hot mix implementation would increase or could be adapted to reduce black carbon.