Capping off what was left behind

An excavator drops trees into an industrial chipper after they were removed from a landfill site Mar. 1, 2011 at Scott Air Force Base, Ill. The base landfill that operated from the 1940's until 1976 is being capped as part of a $20 million project. The 36 acre landfill engineered capping will consist of a one-foot thick gravel layer for methane gas collection, a geosynthetic liner to cover all of the landfill waste and prevent future contact with the waste, a drainage layer to funnel rainwater off of the liner, and two feet of clean soil to serve as a protective layer for the liner and to support vegetative growth. As part of the landfill capping project, the first phase is to remove the trees that have grown on top of the landfill. Capping the former base landfill is part of the Environmental Restoration Program efforts to meet the Air Force's goal of having remedies in place at contaminated sites by the end of 2012. (U.S. Air Force Photo/Staff Sgt. Brian J. Valencia)