The single biggest disadvantage of sanitary landfills is that they produce methane, a greenhouse gas at least 28 times more potent than carbon dioxide at trapping heat. But that’s only one item on a long list. Sanitary landfills also risk contaminating groundwater, consume large areas of land permanently, lower nearby property values, and require costly monitoring for decades after they stop accepting waste.
Methane and Greenhouse Gas Production
When organic waste like food scraps, paper, and yard trimmings gets buried in a landfill, it breaks down without oxygen. That process generates landfill gas, which is roughly half methane and half carbon dioxide. Methane is the bigger concern because its warming effect is at least 28 times stronger than carbon dioxide over a 100-year period, according to the EPA. Even landfills equipped with gas collection systems can’t capture every molecule. Some escapes through cracks in the cover soil, around the edges of collection wells, or before the collection system is even installed.
Large modern landfills often install systems that capture methane and burn it for energy, but smaller or older sites may simply flare it off or let it vent. The result is that landfills remain one of the largest human-caused sources of methane emissions in many countries.
Groundwater Contamination From Leachate
Rainwater filtering through buried waste picks up a toxic cocktail called leachate. This liquid can contain heavy metals like chromium, zinc, barium, lead, cadmium, and mercury, along with traces of pharmaceutical compounds, industrial chemicals, and dissolved organic matter. If leachate reaches the soil and groundwater beneath a landfill, it can contaminate drinking water supplies for surrounding communities.
Sanitary landfills use engineered liner systems, typically thick plastic sheeting made of high-density polyethylene, to prevent leachate from seeping out. These liners are durable. Lab and field testing suggests a properly buried liner shielded from heat and sunlight can last several centuries before significant degradation occurs. The primary threat is oxidation, which leads to stress cracking over time. But even a well-made liner only needs a single defect, a puncture during construction, a seam that wasn’t welded correctly, or damage from settling waste, to allow leachate through. The risk is low in any given year, but landfills sit on the landscape for generations.
Land That Can Never Be Fully Reused
A sanitary landfill permanently changes the land it occupies. Federal regulations in the U.S. require that once a landfill closes, a notation is recorded on the property deed in perpetuity, alerting any future buyer that the land was used as a landfill and that its use is restricted. No future development can disturb the final cover, the liner system, or the monitoring equipment. That rules out most forms of construction, agriculture, and excavation.
Some closed landfills are converted into parks, golf courses, or solar farms, but the options are narrow. The land can’t support structures with deep foundations, and any planned use has to account for ongoing gas venting and potential settling of the waste mass beneath the surface. In densely populated areas where land is already scarce, dedicating hundreds of acres to a use that locks them out of productive development for centuries is a significant cost.
Decades of Post-Closure Monitoring
Closing a landfill doesn’t end the expense. U.S. regulations require a minimum of 30 years of post-closure care, during which the operator must maintain the cover system, manage stormwater, monitor groundwater quality, and keep gas collection equipment running. State regulators can extend that 30-year period if conditions warrant it.
All of this costs money. Landfill operators are required to set aside financial assurance, essentially a guarantee that funds will be available for post-closure care even if the company goes bankrupt. For municipalities, that means budgeting for a facility that generates no revenue but still demands regular spending. When those costs are factored in, the true price of landfilling is considerably higher than the per-ton tipping fee suggests.
Odor and Quality of Life for Neighbors
Landfill odor is more than a minor annoyance. Residents living near landfills describe the smell as rotting food, decaying carcasses, chemical fumes, and burning gases. Research on communities bordering landfills found that the strongest odors typically come from fresh garbage spread on the working face of the landfill, not from the buried waste underneath. The buried material produces hydrogen sulfide (the classic rotten-egg smell), but it’s actually part of a broader mixture that includes ammonia, mercaptans, and various organic compounds.
These odors aren’t just unpleasant. Studies have linked living near landfills to increased reports of headaches, nausea, and respiratory irritation, though separating the effect of smell from the effect of actual chemical exposure is difficult. What’s clear is that for people who live within a few miles of an active landfill, the daily experience of unpredictable bad smells meaningfully reduces quality of life.
Dropping Property Values Nearby
The financial hit extends to homeowners in the surrounding area. Research on rural residential properties near landfills found that homes in close proximity lost roughly 6% of their value on average. One study in Minnesota estimated the impact was about 12% at the landfill boundary and around 6% at a distance of one mile. The effect tends to fade with distance, but for families whose largest financial asset is their home, even a few percentage points represents thousands of dollars in lost equity.
This decline reflects not just odor but the general stigma of living near a waste facility, concerns about truck traffic, noise from heavy equipment, and worry about long-term environmental contamination. These property value losses are rarely compensated, and they fall disproportionately on lower-income communities where landfills are more likely to be sited.
Wasted Resources That Could Be Recovered
Perhaps the least visible disadvantage is what landfills represent in terms of lost materials. A significant share of what gets buried, including metals, glass, paper, plastics, and organic matter, could be recycled or composted instead. Every ton of aluminum cans or cardboard buried in a landfill is a ton that has to be replaced by mining new ore or harvesting new trees. Landfilling treats these materials as worthless when they still have economic and environmental value.
Composting food and yard waste would also reduce the volume of organic material generating methane underground. In this sense, the greenhouse gas problem and the resource waste problem are connected: diverting organics from landfills addresses both at once. As long as landfilling remains the cheapest and most convenient disposal option in many areas, though, the incentive to recover materials stays weaker than it could be.