Answer Man

Underground ‘fire’ at landfill is a misnomer

Q: Why can’t the Bridgeton Landfill underground fire be extinguished? Where does the fire get oxygen to continue burning?

H.T., of Columbia, O.H., of O’Fallon, et al.

A: Repeat after me: Catgut guitar strings never contained cat gut.

Panama hats originated in Ecuador.

The Bridgeton Landfill fire is not a fire — at least, not in the way you typically think of it.

Yes, in this case you have to forget what you likely remember from seventh-grade science class, says Russ Knocke, vice president of communications and public affairs for Republic Services in Phoenix, Ariz., which owns the landfill. He knows that when most people hear “fire,” they immediately think of the classic combustion triangle with its three sides of heat, fuel and oxygen. Put enough of those ingredients together, and you’ll get the smoke and flames you’ve seen in every blazing inferno that has ever led the 10 p.m. news.

If that recipe were producing the current situation in Bridgeton, Republic probably would be doing a happy dance, Knocke said. The company could pour water or spread foam or shut off the source of air to snuff it out, just as firefighters do to extinguish your run-of-the-mill house or trash fire.

But it can’t. Instead, deep below ground, a mountain of densely compacted waste dumped over 20 years is slowly decomposing, giving off heat as rotting waste does. But for reasons not understood, the decomposition here went out of control in some areas and began producing twice the amount of heat you’d find at a “normal” landfill. For nearly five years now, these abnormal levels of heat have continued to spread.

This migrating heat pocket is the “fire” you keep reading about in the headlines, but there’s no flame — and no oxygen to speak of down there to feed it, Knocke said. To science geeks, it’s known as an exothermic chemical reaction, but journalists and politicians don’t want to hit readers and constituents with incomprehensible terms so “fire” remains the word of choice. Either way, the conclusion is obvious: It takes far more than sticking a hose into the ground to put one of these babies out.

“It’s a chemical reaction, and you have to handle chemical reactions in a completely different way,” Knocke said. “The goal is to keep it in the same area, keep it managed as it has been, and keep it isolated. Over time, it will self-extinguish.”

To get a better grasp of the phenomenon, Knocke suggests thinking of it as a compost pile you might start in your backyard. As you add yard waste and banana peels, the stuff in the pile decomposes. As it does, the process produces a low-grade heat. If you’d stick a thermometer in a so-called normal landfill it might register about 135 degrees.

But the Bridgeton Landfill and others around the country have turned into sort of compost piles on steroids. In December 2010, Republic started to discover abnormal temperatures that at one point climbed to above 300 degrees, more than double what is considered normal. Worse, this reaction was spreading — and continues to spread — to sections that had been rotting away at the more conventional rate.

In the world of waste management, it’s a relatively new phenomenon. Of the 300 landfills Republic owns, the company has experienced the reaction only a “handful of times.” Even now, industrial and academic groups such as the Environmental Research and Education Foundation are trying to uncover what causes these reactions to start.

“I don’t think the industry saw as many reactions a few decades ago as maybe they have in the last decade or so,” Knocke said. “Does that have any sort of implication societally? Are things being disposed of that when they come together and decompose in a landfill such that it’s a potential factor for the start of a reaction? Or is it something altogether different? I don’t think — at least in the context of Bridgeton — anyone knows.”

Once owned by Allied Waste, the Bridgeton Landfill is an approximately 52-acre waste repository that lies at the base of Lambert-St. Louis International Airport just to the west of the airport’s longest runway. It was allowed to start accepting waste on Nov. 18, 1985, and, during the next 20 years, the waste piled up more than 300 feet high. That fact alone no doubt played a role in the current situation, Knocke said.

“If you’re operating an active landfill every day, you’re compacting that waste and trying to create as much capacity as you can so the landfill services that community for as long as it possibly can,” Knocke said. “So waste is packed in and packed in and packed in. As that happens, one, there’s no oxygen and, two, it’s warm. Waste is a tremendous heat insulator.”

Still, there was no sign of trouble in late 2004 when the landfill was closed to further dumping to keep it from attracting birds that interfered with airport operations. But after purchasing Allied Waste in June 2008, Republic reported on Dec. 23, 2010, that elevated temperature readings were being found on some of the wells that allow gas to be extracted from the rotting refuse. Testing soon revealed the escaping gas to have elevated levels of hydrogen and carbon monoxide, an indication of a “subsurface smoldering event,” as the Missouri Department of Natural Resources calls it.

As the situation was monitored over the next three years, an even more alarming discovery emerged: The “fire” was spreading northward toward the adjacent West Lake Landfill, where radioactive waste had been illegally dumped in 1973 and which has since become a Superfund waste cleanup site. Fears grew that if this chemical reaction from Bridgeton invaded West Lake, it might release radioactive fallout into the air that would spread throughout the region. In March 2013, Missouri Attorney General Chris Koster filed an ongoing lawsuit against Republic, accusing the company of violating state environmental laws.

Both the “fire” and the fear continue to this day. In reports released in September, Koster said experts found that the ECR is still out of control and heading toward West Lake, a quarter-mile away. Based on a St. Louis County emergency plan, school districts in north St. Louis and St. Charles counties recently sent letters assuring parents that their children would be either sheltered at school or evacuated if an emergency arose from the release of radioactive gases from the landfill.

But while it doesn’t know what would happen if the West Lake site were breached by the Bridgeton ECR, the Environmental Protection Agency says its most recent temperature readings and analysis indicate that the smoldering underground has been contained. In addition, a new report from the U.S. Department of Health and Human Services concludes that the Bridgeton Landfill poses no health threat to the region.

Republic agrees. The company says that in 2013 the reaction came within 1,200 feet of the toxic West Lake Landfill, but the advance northward then stopped. Temperatures have decreased. Today, the closest hot spot is 2,500 feet away, the company says. In the past two years, Republic has spent $150 million to track and isolate the smoldering, which, Knocke says, has made it “physically impossible” for the ECR to reach West Lake.

Instead, the smoldering does continue to move at a rate of about 6 inches per day, but in a south-southwesterly direction, which is 180 degrees away from West Lake. In addition, Republic has capped the site to eliminate the emission of smelly gases and has installed a wastewater plant, numerous cooling units and gas extraction pumps. Although he can’t predict when, Knocke says the “fire” eventually will flame out, as it were.

“The Bridgeton Landfill is in a limestone quarry, which is common in Missouri,” Knocke said. “The walls and floor are limestone, which is advantageous because this reaction is moving in the direction of a limestone quarry wall. But limestone is porous, which is another good thing. The limestone is helping absorb some of the heat so when you begin to remove heat from the reaction, that’s a helpful tool in keeping the reaction contained and isolated. So it will continue to cause waste to decompose at an accelerated rate but it will at some point run out of that fuel source in that area. As we extract heat, it’s going to have less potency and capacity to move. So over time, it will self-extinguish.”

Yet officials are taking no chances. On Thursday, Missouri Sens. Roy Blunt and Claire McCaskill along with U.S. Reps. Ann Wagner and William Lacy Clay introduced legislation that would transfer oversight of the West Lake Landfill from the EPA to the Army Corps of Engineers. Republic opposes the move, saying it would further slow a final solution, but, like the fire in Bridgeton, it’s a burning issue that apparently will continue to smolder.

Today’s trivia

In what city would you find the National Quilters Hall of Fame?

Answer to Friday’s trivia: Donald Franchot McHenry grew up in East St. Louis during the 1940s and early ’50s, earning degrees from Illinois State and Southern Illinois University Carbondale. When he was just 26, he began working for the U.S. Department of State, where his stature quickly grew. In September 1979, President Jimmy Carter named him to replace Andrew Young as the country’s 15th — and second black — ambassador to the United Nations. Last year, McHenry, 79, stepped down after 23 years as a director at Coca-Cola, but he is still listed as a distinguished professor of diplomacy at Georgetown University in Washington, D.C.

Roger Schlueter: 618-239-2465, @RogerAnswer