It will compost, anaerobically, producing more methane and VOCs, and as they do, they create a sludge, that often picks up acid and other contaminants, which quick create leaks in landfills.
https://www.clf.org/blog/all-landfills-leak-and-our-health-a...
> The water that gets into landfill cells picks up contaminants from the waste and becomes “leachate.” What’s in the leachate depends on what’s in the landfill, but some chemicals can be counted on, such as volatile organic compounds, chloride, nitrogen, solvents, phenols, and heavy metals.
> The safeguards intended to prevent leachate from escaping a landfill cell – pipe collection systems in newer landfills and the plastic and clay liners mentioned above – fail over time. This toxic brew of “garbage coffee” leaks out of the landfill and seeps into groundwater – contaminating wells and waterbodies.
Anecdotally, 3 of 4 landfills in my area have ongoing leaks from leachate and now strictly police cardboard and other organic non household trash from the sites.