Steve Gravelle, CR Gazette –
The fire at Iowa City’s landfill may bring changes at other landfills in the state.
“We’re probably going to ask these questions,” said Alex Moon, supervisor of the Iowa Department of Natural Resources, solid waste program. “How big is the cell, do you really want to leave that much exposed.”
The Iowa City fire, smoldering through its fourth day, apparently started when burning material in a load of waste dumped Friday afternoon ignited the “drainage layer” of chipped tires, which continues to burn.
“If (the chipped tires) had been covered with garbage this would have been far more unlikely,” Moon said.
Moon said the landfill meets DNR standards, but those standards may change to prevent future fires. He said the fire is in a recently opened new cell where crews spread a three-to-four-foot-thick layer of chipped tires over the entire 14-acre area. About half the cell is still open, leaving the rubber exposed.
Landfill operators are required to install a drainage layer when opening a new cell. The layer is designed to protect the underlying plastic liner and clay base while allowing water to drain. Drainage layers may also be made of sand or gravel.
“We really encourage people to use tire chips” to take used tires out of the waste stream, Moon said. But he said the DNR may issue guidelines after the fire to limit the exposure of tire-chip drainage layers.
“Maybe one thing we can learn from this is to avoid putting down all your drainage layer at a time,” Moon said.
Joe Horaney, spokesman for the Cedar Rapids/Linn County Solid Waste Agency, said chipped tires are used in the drainage layer of the County Home Road landfill north of Marion. But the cell currently in use is older, and its drainage layer is buried about 20 feet below the surface.
Incoming loads are inspected by landfill workers at the scales and the dumping area, Horaney said. If smoldering material is found in a load it’s dumped away from other waste and quickly covered with water, then dirt.
“We have not had (a fire) like that at the County Home Road location that anyone can remember,” at least 25 years, Horaney said.