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Current pressure cooker bombs typically use ammonium nitrate. It’s the single most common base compound for homegrown explosives around the world. About 65 percent of the 16,300 IEDs detonated in Afghanistan in 2012 used it. When Timothy McVeigh bombed the Alfred P. Murrah building in Oklahoma City, he used some 4000 to 5000 pounds of ammonium nitrate. And the explosion that killed 14 people in West, Texason April 17 was the result of 270 tons of ammonium nitrate that had apparently decomposed and ignited, the result of nothing more than time and heat. Ammonium nitrate is now banned in Afghanistan, where it had once been in widespread use by local farmers.
According to Popular Mechanics there may be a way to minimize the use of this fertilizer in terror acts.
The solution may be a slight change in its chemical formula just enough to make it useless in bombs? That’s what Fleming wants to do.
In January 2012, the Joint IED Defeat Organization (JIEDDO), a counter-IED task force within the Pentagon, put out a request for ways to neutralize ammonium nitrate’s effectiveness in explosives. In March, Fleming submitted his proposal: Add iron sulfate. It’s a common enough substance. Iron sulfate is a waste product at steel foundries, for example, which produce 4 to 6 tons of the stuff for every ton of titanium. Iron sulfate is already used as a soil conditioner in the more desert like areas of the American West, where the ground tends toward the overly alkaline. If anything, Fleming says, Afghan farmers should benefit from the additive.
The real reason to do it, though, is this: To unlock the destructive chemical potential of ammonium nitrate, bomb-makers have to process it. (Fleming has asked us not to specify how; suffice it to say, it’s a low-tech procedure.) And if iron sulfate is present when the would-be bombers try to do this chemistry, it sets off an irreversible reaction. The sulfate and the nitrate ions switch places. Iron sulfate becomes iron nitrate, and ammonium nitrate becomes ammonium sulfate. What was once the ready-made bomb fuel is now inert.
Fleming’s proposal wasn’t funded. So he worked on the project on his own time and budget while working at Sandia National Labs (he retired this past January). He ran tests to confirm the mid-processing ion swap, and when his research was ready to be released, Fleming asked Sandia’s lawyers to waive all patent and royalty rights. “There’s nothing in it for me,” he says. “I just don’t want to see any more people die from these things. I’ve seen way too much death and dismemberment in my time at Sandia training soldiers to identify IEDs. Too many kids with their legs gone.”
Of course, Fleming’s proposal is just that-a proposal. Although JIEDDO already passed on the idea once, if that organization, or some other government or private entity picks up where he left off, they’ll have to sort out the proper ratio of iron sulfate to ammonium nitrate, and possibly set up a red team-an expert group that would try its hardest to detonate the compound or extract the iron sulfate, just to see if it can be done. (Fleming isn’t worried about either-all of the chemistry indicates a lack of detonation, and since the soil conditioner is just as water soluble as the fertilizer, it would take an incredibly well-outfitted lab to separate them.)
There are costs to consider, too, and questions of enforcement, and regional logistics. The fertilizer won’t be sold everywhere because the new mix wouldn’t be suitable for less alkaline soil-for instance, iron sulfate might not have been a feasible additive for the ammonium nitrate that ignited in Texas. Unless every fertilizer-maker were to switch over to iron sulfate, it’s conceivable that would-be bomb-makers would just seek out the brands without it.
But anything that lessens the supply of bomb components helps, and it’s hard not to root for Fleming, and for his idea. It’s an open-source idea with no strings attached, and one that could save countless lives. The former government researcher hopes it could improve some lives, too. Fleming runs a 5-acre farm, and he knows soil, and fertilizer.
“On its own, ammonium nitrate is almost like heroin. It damages the soil, and increases soil erosion, and so you have to use more and more of it,” he says. “But those poor farmers in Afghanistan, they can’t even get that anymore. Their choices were even worse. This is the best of both worlds; a reduction of IEDs from ammonium nitrate, and a good fertilizer.”