| The residual material no longer produces methane, and leachate is much reduced. |
| Devices called lysimeters are sometimes inserted into the ground to collect subsurface water, called leachate. |
| Sludge in the landfill ferments and produces polluting leachate and greenhouse gases. |
| It also provides a means of collecting most of that leakage and therefore is a second leachate collection system. |
| All landfills, including those not in use, produce landfill gases and leachate, or water that has permeated the surrounding soil. |
| True, leachate can lead to many lesser health problems and environmental effects that the EPA did not assess. |
