Iowa City Entombs Landfill Fire in Clay

Iowa City Public Works Director Rick Fosse couldn't have been happy with the amount of rubber available to fuel the 7.5 acre Fire, which has burned incessantly on Memorial Day weekend.

He can however be thankful for another nearby material: clay soil.

It is clay soil that was used as the cap for the , allowing the city as city officials wait for it to burn itself out.

Meanwhile, a clay layer below the burning rubber in the landfill cell has kept the pyrolitic oil generated by liquidating shredded tires from seeping into the water supply, allowing it to be instead collected and trucked off of site.

And, now, as if it hadn't done enough already, clay soil is being used to barricade the cell to prevent the fire from spreading to other parts of the landfill.

"We have a lot of clay earth on site," Fosse said. "That was the material we had available and it works very well."

Fosse said city workers have been barricading the points where the burning landfill cell connects with other nearby cells on the eastern edge and southwest side. He said they are doing so by actually digging all the way down through the trash to the bottom layer of the landfill cells and inserting a wall of clay soil in between the cells.

"It's like a vertical clay wall that we're cutting in," Fosse said.

Fosse said this is part of an overall effort this week to contain the fire. Other efforts include tirelessly searching for hotspots near the affected area. This means the teams have to search under layers of trash and earth, which must be excavated, tested for heat, and sprayed with water before the teams can move on to the next spot.

Efforts are also being made to collect the aforementioned pyrolitic oil, which is being stored in an on site lagoon. Fosse said as of June 8, the city had trucked 38,000 gallons of the oil away from the landfill site, sending it as far away as Nebraska, Ohio, Missouri and Canada to be incinerated. He said 80,000 gallons of the oil still remained as of that date, however.

Fosse said if the city does rebuild the landfill cell damaged by the fire, it could potentially do so on the already existing clay layer, which, despite some of it being turned into crude brick by the intense heat of the fire, still for the most part sits resilent and moist underneath.

Geoff Fruin, assistant to the Iowa City City Manager, said that from an administrative standpoint, the city is already investigating what it can do to defray the estimated $6 million in damages caused by the fire's destruction. Included in this will be possible insurance rewards, but the insurance company's investigators won't be able to start their work until the fire has died down, which could be weeks from now.

After the fire finally is extinguished, Fruin said the city will also start the long process of analyzing its response to the crisis as well as how it should change how it does things at the landfill.

"We're going to have to review the design decisions that went into that new landfill cell, and determine what different approaches we can take next time when building a new cell," Fruin said. "We also have to look at our fire mitigation strategies we have from an operational standpoint, and how we can modify them to prevent this from happening again."

Fruin said there was at least a brief sense of relief when the city staff heard the clay soil cap had been completely set into place on Sunday.

"The fire is still burning, and there's still considerable risk out there on the site for the fire spreading, and there are still some very pressing needs on site," he said. "But certainly when we got the call on Sunday that the clay cover that had been applied to the site, that was a good feeling."

Fruin also cited the work of employees at the landfill and how they have responded to the challenges on site, many of them working seven day weeks in a challenging environment.

"The employees that have worked on the site have just been phenomenal," Fruin said. "Truly, it should make you proud. Certainly it makes us proud in the city manager's office to see them respond like that."