Excerpt from What We Leave Behind

Recycling Depleted Uranium (p. 314)

From chapter "Technotopia"

There’s another big obstacle to an ecologically sustainable industrial technotopia: war.

Supposedly green military technologies have been making headlines more and more over the last couple of years. Wind turbines constructed at Guantanamo Bay, programs to develop a bio-fuel for fighter jets, and a hybrid-electric military jeep are among the most notable examples. It’s up for debate whether such initiatives demonstrate simply a series of shallow PR moves or a military recognition of peak oil and a looming energy crisis. In either case, most thinking people realize that war and sustainability don’t go together.

In the technotopia I’m describing, the people of the future have dealt with finite supplies of various valuable metals by instituting a perfect cradle-to-cradle approach to industry, similar to that proposed by William McDonough (never mind that it still, several hundred pages later, is not going to happen). All manufactured metals are carefully fabricated, tracked, and recycled when a product reaches the end of its use (I almost wrote life span, except of course products aren’t alive: I mention this to show how deeply we’re all enculturated to identify the products of this culture with life). We can talk about how (im)plausible that is at the best of times, but war is not the best of times. War materiel, from bullets and uniforms, to missiles and bombs, to tanks and fighter jets, is built to be destroyed. There’s a good chance that in a time of war almost anything built by or for the military could be torpedoed, sunk, burned, blown up, nuked, or otherwise obliterated. That’s not a good way to build a cradle-to-cradle industrial system. In fact, various munitions are built specifically to be destroyed and converted into dust and unsalvageable wreckage. They are designed to become waste, and to waste something—or someone—else. The worst munitions don’t just physical destroy the target—they irradiate it. They also irradiate the battlefield, and the landscape. Case in point: depleted uranium.

Depleted uranium is primarily a byproduct of the processes that “enrich” uranium used for nuclear warheads and reactor fuel. The military mostly uses depleted uranium for two purposes—armor and ammunition. The reason bullets are commonly made of lead is that lead is a fairly dense metal. Bullets are made out of dense materials so that a small projectile can carry of lot of energy. The less dense a projectile is, the less damage it can cause—think nerf guns. Well, depleted uranium is about twice as dense as lead, which means it can do a lot of damage, and is especially effective in armor-piercing munitions. It’s also “self-sharpening,” meaning that when a DU projectile strikes a hard object, it fractures into smaller, sharp shards. Most of a projectile is turned in to dust, but the remainder— which may weigh several pounds in larger shells—is a solid lump of uranium left on the battlefield. DU is also pyrophoric, capable of spontaneous ignition. This means when an armor-piercing DU penetrator is fired at an armored vehicle, it may punch through the armor and, by the time it enters the crew compartment, be fragmented into a radioactive dust that will catch fire. Just what you want in an armor-piercing shell. Not what you want if you care about a non-irradiated populace and landscape.

By the 1970s, the US had stockpiled about half a million tons of depleted uranium. Since DU is radioactive, it was proving expensive to properly store such large amounts. However, at that time the Pentagon was searching new materials for armor-piercing munitions, and realized it could, as it were, kill two birds with one stone—make more effective weapons, and get rid of large and expensive stockpiles of DU. Isn’t recycling grand?