Is it possible to go landfill free?
Would it be possible to reclaim the land currently used for non-radioactive landfills (excluding Yucca Mountain and other radioactive waste dumping sites)?

Technically? Yes.

Practically? It would cost a lot of money that governments are not willing to spend without really really convincing reasons.

There are thousands of bacteria and fungi that could be used to break down toxic fossil fuel derived compounds, plastics, and uptake heavy metals converting them into less dangerous molecular forms. These, in addition to revisiting landfills to collect metals, plastics, and glass that can be recycled would turn landfills into glorified composting yards. At that point, depending on the amount of remediation needed, the remaining degraded bits could be used in agriculture as compost to be tilled into fields. This may just be for the future though. Unfortunately, this alone will not solve the problem of landfills given humans tend to create waste rapidly. There are still many studies to be done on microbial and fungal ecology as to see the long term effects of introducing these microorganisms into these areas. They do, however, provide a ray of hope.

Landfill alternatives include:

• Pyrolysis (leading to the creation of biochar for agriculture!)
• Incineration to generate electricity (can be combined with pyrolysis)
• Plasma Arc Gasification (a.k.a. PGP - Plasma Gasification Process) 
• Mechanical Biological Treatment (includes: Composting and Anaerobic Digestion)
• Waste Reduction Programs (recycling and materials reclamation)

But what can you do?
Reduce your own waste, compost, and fight for changes in your city, county, and state’s waste management efforts. Talk to university professors, green technology experts, green economists, and environmental safety experts willing to write personal testimonials about how changing waste management practices will lower costs over the next 10-100 years, improve quality of life and overall health, and provide jobs and revenue to the area.

Explain that cities/counties could SELL the compost for profit.
Explain that cities/counties could SELL reclaimed recyclable materials (metal and glass are two big ones) for profit.

Laws that help with these efforts are already in effect in the state of California. What is your state doing?

Remember: The fastest way to make a change in your community is to be involved and start acting on the change yourself!