Many European countries (Germany, Sweden, Norway, etc) don't allow landfills for common household trash. The solution obviously has many facets. Mostly it breaks down to waste separation (e.g. different bins for plastics, compost and paper that are emptied for free, with high fees for the rest to encourage people to separate), recycling what you can and burning the rest. Burning trash produces energy and you can deal with produced gases at one central location, what's left after burning is easy to landfill because it's much less volume and basically doesn't decompose.

Many landfills [0] now recover the methane, and treat it, or burn it in generators to create power. They can sell the power, and change the methane to carbon dioxide (which is less of a greenhouse gas)

In Madison, WI, [1] they create enough power to offset all the energy the county operations use, plus create CNG for their heavy equipment at the landfill to run on.

[0] https://en.wikipedia.org/wiki/Landfill_gas_utilization

[1] https://isthmus.com/news/news/dane-county-might-sell-the-met...

You can burn the garbage for energy instead. Then you don't need as much oil from the ground.

It also takes care of the plastic problem, since it burns the plastic very cleanly.

Not sure how effective it is, but it's possible to collect methane from landfill and use it to generate heat and electricity. From my understanding the emission from burning it are way better then just letting it leak into the air.

My university had a big methane line run from a landfill 2 towns over and used it in the cogen plant to generate power and steam for heat.

It's not that much. People do landfills all over the world without much economic impact.

And you can recover the methane from them, what requires a small investment, and has a low, but positive ROI.

Diverting compostable material to an industrial compost operation is one option that can save money on building new landfills. Another is just good landfill design that ensures good drainage & aeration, which is a well understood problem but probably not always done well.

I believe some landfills and dairies capture methane. If there were a GHG pollution tax, they could save a lot of $ capturing excess waste methane. As is, I wonder if it's a neutral or cost saving to capture methane?

Bury the trash deeper, so the methane is effectively sequestered?