Polyblend, a fine powder of recycled modified plastic, has proved to be a good material for:
1. making tubes and pipes
2. making plastic sacks
3. use as a fertilizer
4. construction of roads

Which of the following is an innovative remedy for plastic waste?

1. Burning in the absence of oxygen

2. Burying 500 m deep below the soil surface

3. Polyblend

4. Electrostatic precipitator