Mulchpocalypse 2012: How Did a Pile of Bark Turn Into a Fire-Breathing Dragon?

The mulch fire was pretty much all anyone talked about last week, other than Pat Summitt's retirement. It was understandable, given the thick wood smoke that spread across town for days, making living rooms smell like fire pits and lungs feel like they'd smoked a pack of cigarettes.

Finally, by Tuesday morning, the fire was officially "out."

"To be honest with you, the fire's probably been out since at least [last] Thursday," says Randy Greaves, the owner of Shamrock Organic Products, the site of the fire. "Since then they've basically just been looking for hot spots, you know. It's a precautionary measure."

The city spent over $33,000 fighting the blaze last week, which started on the morning of Sunday, April 15. Greaves says he inspected the facility off Middlebrook Pike early that day, at around 8:45 a.m., and saw nothing amiss. By 11:32 a.m., however, the flames had jumped from mulch piles across a 15-foot driveway to piles of brush.

"It's hard to start something that big with an ember. Spontaneous combustion doesn't go this far," Greaves says. "I am very suspicious of the source of this fire."

Mulch that is piled up more than a few inches deep starts to heat up as it decomposes, which can lead to fires starting via spontaneous combustion, and Shamrock has had small mulch fires in the past. However, Greaves insists there is no way spontaneous combustion could have started something this big. He points out that homeless people in the railway easement near Third Creek often start fires near his property, and he often sees them smoking.

"I used to call the police on them, but it would just make them mad. They'd come on to my property and smash windows and steal tools—and start fires. So I stopped calling the police," Greaves says.

Whether the fire started from spontaneous combustion, a carelessly tossed cigarette butt, or something more nefarious, Greaves insists the scope of the fire isn't his fault. If he hadn't been contractually obligated to take in some much brush after last year's storms, he says, he never would have had so much mulch and brush able to catch on fire.

"Until 2011, I sold everything I processed—100 percent of everything for 18 years," Greaves says. Shamrock has had a contract with the city to process its brush and leaf collections since 1994, and is currently in the middle of a 10-year contract that concludes in 2016. When last year's storms hit, Greaves says his daily collections went from around 140 tons to nearly 500 tons.

"The amount coming to me tripled without warning, for five months," Greaves says. Per his exclusive contract with the city, Greaves had no choice but to take all the debris, and require all his employees to work unloading trucks, instead of loading up other trucks with saleable mulch.

"My baseline for volume in an average year is 25,000 tons of brush and 9,000 tons of leaves. During the five months following the storm, I received an incremental 20,000 tons of brush," Greaves says. "The bottom line is the storm overwhelmed my facility, but I fulfilled my contract with the city, within code and under the ordinances." Greaves points to two recent fire inspections that showed no issues with Shamrock. And while there have been 158 calls to the fire department about possible fires from Shamrock over the years, Greaves says, "Those are 158 calls, not 158 fires. ... A competitor can call this in. A person who's driving by on the interstate and doesn't know the difference between smoke and steam coming off the piles of mulch can call this in."

The city's director of public service, David Brace, says it makes sense for the city to contract with a mulch processor located in the heart of the city as opposed to out in a rural area, where the smoke might have caused fewer problems.

"It cuts down on emissions from our trucks, we save on fuel, and it cuts down on labor," Brace says.

Of course, given the cost of the fire and the environmental cleanup on Third Creek still to come, it's unlikely any money will be saved this year. The city announced Friday its engineering department has created an aeration system in the creek to help manage mulch runoff and improve conditions for fish; however, the Tennessee Department of Environment and Conservation wants more.

In a press release, David Hagerman, an engineer with the city's stormwater management department, says, "This is just a partial solution, but we want to do everything reasonable to keep pollution in the water to a minimum. TDEC came out this morning and was very appreciative of what we were trying to do and offered suggestions, but there will need to be a permanent containment system in place onsite once the fire is extinguished."

As of Tuesday, the fire department had not yet issued its final report about the cause of the fire.

"I hope everyone will be patient and wait for the report. I think that I will be exonerated completely," Greaves says.