Dear student,
As we know that plastic is non-biodegradable substance i.e. if thrown in open it will not decompose easily it takes thousands of years to degrade. After throwing plastic garbage trash collectors, collects the trash and dump them into landfill. At the landfill, some trash might be burned, some buried under soil and some are recycled in this way waste management companies make sure to decompose all waste properly and efficiently.
Regards,