By Timothy D. Stark
Q: The following photo shows a landfill cover with a gray material exposed. Is this good? If not, what should be done?
A: A close-up of the gray material indicates that it is the geomembrane that is part of the final cover system for this landfill. This is not good and was probably caused by the cover soil sliding off the top of the geomembrane because of the steep slope. If so, the geomembrane should be inspected to ensure there are no defects in the geomembrane and then carefully covered with soil to protect the geomembrane from environmental factors.